remove deprecated class
we must return empty element instead of null
overrides
cleanup
IDEA-128588 Context menu in editor does not open during indexing
removed unused arrays settings
updated help_id for PyCharm Education
Merge remote-tracking branch 'origin/master'
completion inside lambda: accept 'reference' non-physical statements
Refactoring: common git&hg branchPopup and sync branch settings moved to dvcs

 * common methods and fields moved to parent class to dvcs;
 * common branch sync settings interface added to unify several cases;
 * generics for Repository added;
 * annotations added;
unnecessary method removed
Tracking hg branches and bookmarks synchronously implemented

* appropriate setting added to hg project configuration panel;
* branch actions modified and now accept list of sync tracked repositories;
* branch widget updated;
* annotations added;
Merge remote-tracking branch 'origin/master'
Merge remote-tracking branch 'origin/master'
Added escaped quotes support to CommandLineTokenizer