[vcs] Commit dialog: move the changelist selector back.

Let the changelist selector appear in its default place: above the
changes browser.
This would let the right panel occupy a bit less place.
Relates to IDEA-90202.
don't highlight String.class in annotations
smart complete full qualified types
strange restriction in reference copy/paste
IDEA-104500 Gradle: Allow to reuse common logic for other external systems

Add *.jar file with external system-specific project resolver class to the classpath