IDEA-121060 Multiple carets: comment/uncomment works incorrectly

Fix for 'comment by block comment' action
IDEA-121060 Multiple carets: comment/uncomment works incorrectly

Fix for 'comment by line comment' action
IDEA-121060 Multiple carets: comment/uncomment works incorrectly

fixed existing tests
fix test (following IDEA-124928)
fix blinking test
IDEA-122513 Can't expand single character property in Spring config