[Forwardport] 2.4: Update types and add GRB test

on metadata init first time, settings can stay empty for a long time
if git clone is slow.

[forwardport] Add nodepool validator

Fix flaky globalrole test

Tests now retry updates if a 404 is encounter. It is possible
that listers are not up to date immediately after creating
object, result in not found errors.

Rename tests and made changes to vsphere provsiioning cases to use exsiting libraries for validation

Make ListNamespaced request in nodepool controller

[master] docker-machine version bump

Create global roles

It is now possible for admins to create global roles. Admins are
also able to edit non-builtin roles. Prior, admins were confined
to only using global roles that were predefined by rancher.

ExternalID is the distinguishedName of a user, which is being used as the baseDN
in ldap search query in RefetchGroupPrincipals. This doesn't need to be split on `\`.
That split is only for when we're using some field that has "logindomain\username"
format. Splitting incorrectly on `\` removed a part of the distinguishedName leading
to ldap errors

Removed unused code