(cherry picked from commit 284e06c0), IDEA-CR-25271, r=Peter.Gromov

IDEA-161081

New authentication type `OPEN_SSH` enhances `AUTH_AGENT`. Beside using authentication agent (ssh-agent or PuTTY) OpenSSH config is used to locate identity files that could be used for authentication.

Todo index isn't calculated for library files anymore, but BaseFilterLexerUtil
adds ScanContent to the user data only if it will be needed for both Id
and Todo indexes and it is expected to be removed by the second.

- significantly improves performance for big files, because less matching
schema searches are done

but the speed of highlighting currently is not comparable with the size of the file

- remove old JvmElementActionsFactory#createAddMethodActions;
- remove implementations of above method;
- remove MemberRequest.Method;
- remove actions.kt#createMethodAction.

The cause of the problem was the difference in parsing for different
language levels.

This commit improves error recovery and adds support for stubs for
syntax elements unavailable in older Python versions.
Cases that are covered are necessary for stubs generation
for Python 3.6 standard library. They are discovered by automatic
validation executed by stubs generator in StubsGenerator.kt.

Those are the cases that were fixed:
* A stub for single star argument in Py2 was absent
* Type annotations in Py2 were absent
* Print with end argument in Py2 broke parser
* Exec function as argument in Py2 broke parser
* Async keyword after decorator broke parser

All the cases are listed as test cases in PyUnifiedStubsTest

P.S. It is possible though that more cases will be revealed in future.

`JvmDeclarationUElement` is a temporary replacement for `UElement`

If in the frame there is at least one very long or slow variable, the frame's variable aren't shown. In order to avoid such situations we add an option to load variables asynchronously. At first debugger loads only names of the variables, and after that it sends additional commands and evaluates values of the variables in a separate threads.

WI-38324 Redesign yellow action bar

Made background more neutral for toolbar editor panels

* do not update entire model during rename shelved changelist: it's
enough to update only this tree node;

* join several update requests together;
* if need to execute something after update - cancel all requests and
force update with post runnable (maybe invokeAndWait would be better);

* show rename dialog if only one shelved list was created during action;