Instead of connecting to an object's logs from the LogViewer, we want
to make this component generic so it can be used to display other logs
or text.
Thus, this patch moves the object logs related logic into another
component defined in the pods/Details view.

The plugin's Registry now allows to register routes. This means that
plugins can set up routes and assign components to them.

This patch adds the possibility of setting up routes from the Redux
store, making it easier to extend the default routes.

These changes add the basic support for frontend plugins.
The current functionality is very limited, it currently allows to set up
Sidebar items only.

The plugins are currently loaded from a "plugin/plugins" folder, if they
are defined in the form: "plugin/plugins/MyPlugin/index.js".

We are implementing frontend plugins, and in order to simplify how they
can add items to the Sidebar component, this patch allows to do that
through the Redux store. i.e. besides the regular Sidebar items, the
component will pull extra items that may be defined in the store.

Instead of having to fetch a route for every Sidebar item entry, it
should also support setting the URL directly from the entry.

This will be useful when we allow plugins to set up Sidebar items and
linking them to a certain URL.

There were a few components with unused variables which resulted in
warnings. This patch prevents those by removing the unused variables.

The filter function was defined, but not assigned to the table.

This patch prevents a warning about an unused variable.

There were warnings about the dependency list for some of the useEffect
hooks, but the suggestions resulted in undesired behavior like too many
reloads, etc.

This suppression is a temporary solution until we take a better look
into the issue.

This patch represents no functional changes, but does surpress some
warnings related to unused imports.

Many places were not using strict equality, and thus it resulted in
lint warnings.

The router already determines the URL and component to render, so
this patch adds a new "sidebar" property to the route specification
allowing to also determine which sidebar item to choose (or whether
to hide the whole sidebar).

Note that the sidebar item can still be selected from any component
by the use of the useSidebarItem hook, but having it in the router
specs is more self-contained and doesn't become a requirement for
creating new components.

This hook can be used by any component to select up their desired
Sidebar item.

It will be used in a coming commit.

Now that we can the state for the sidebar from redux, this patch
replaces the sidebar's logic for selecting the right item.
This simplifies that logic a lot, and allows us also to hide the
sidebar when necessary (e.g. in the login view).

These changes add the state, reducers, and actions for dealing with
UI states (particularly the sidebar at this moment).

The actual use will come in later commits.

This is just a cosmetic change, done for consistency.

The BindingDetails view was assigning the item for the button as an
array of items, which is incorrect (it should be only one single
item).

The title in the SectionHeader was getting shrunk due to how the grid
was built, and thus was wrapping its text even when visually there was
plenty of space for it.

These changes make sure that the title has half of the header's width
to expand, which should be enough.

The data for confimap resources can be null/undefined, in which case
the details view shouldn't attempt to use it.

The buttons were being added to the sections regardless of whether the
user was actually authorized to perform their respective action.

These changes implement the authorization check in each button, only
adding them to the UI in case the user has the needed permissions.

This method will be used to verify whether the user has permissions to
perform given actions on a resource. e.g. delete service accounts.

Since many views will offer the ability to edit a cluster object, this
patch adds a convenience button to manage the visibilty and actions of
the EditorDialog.

It will be used in later commits.

This dialog has a few features that are useful when editing
Kubernetes objects, like the documentation, undoing changes, etc.

Besides the needed dependencies for the editor, react-monaco-editor and
monaco-editor-webpack-plugin, this patch also introduces
the react-app-rewired which replaces the react-app original scripts in
order to allow us to configure things like webpack without ejecting
(losing the "magic config" done by react-app).

The actual use of it will come in later commits.

The way that the tabs are used in Material UI leaves a few things to
the caller. So this new Tabs common component aims that providing a
convenience and quick use of the tabs with the respective content
below them.

The actual use will come at later commits.

Some actions related to buttons need a quick confirmation from the user,
so this patch adds a ConfirmButton that will use a confirmation dialog
when the user clicks it. This is convenient since there will be a number
of places using it soon.

The recent changes to have generic cancellable actions and a notifier
for them worked well but allowed only one message a time.
That is not enough if, e.g. an object is being deleted while another
is being updated.

These changes allow multiple actions to be used/notified at the same
time by using an object/map of actions + a stack of notifications.

This patch introduces a dependency on notistack.

Instead of having redux actions/sagas for the deletion, we should have
generic actions with the same start/success/cancelled statuses and
triggering the snackbars as the deletion action did.

This patch accomplishes and also greatly simplifies how the actions and
snackbars work together.

The cancelUrl will commonly be the current location for the
DeleteButton, so it can be used directly from the button instead of
requiring the user component to always pass it down.

Deleting an object/item is an important action that requires user
confirmation. Thus, this patch adds a new component (ConfirmDialog)
that will can be used for the confirmation.

These changes extract the delete button into its own component so it
can be easily reused from other views.

We need to allow the DELETE method in CORS in order to test cluster
objects deletion in dev mode.

This delete button starts an object deletion action that will be done
from the new related saga.

We want to show snackbars when the user e.g. deletes an object, so
this patch adds that functionality for object deletion related redux
actions.

This patch is introduces a sagas managing the cluster objects deletion.
The actual connection to the UI will come in a later commit.

We need to provide the ability to connect to a pod's container shell.
This patch adds that to the pod's details view.

When more than one action was set, the actions would be spread out
through the horizontal space, which doesn't make sense visually.