Ctrl+click navigation added.

 ##KT-5366 Fixed
Minor: OpenEditor string is now a constant string in OpenDeclarationAction class.
Minor: Java code conventions.
TestCase classes are now abstract. AllTests class added for completion.

Minor: excess empty lines removed
Autotesting framework.
Autoimport tests are now automatic.
Tests for navigation performed.
Autotesting framework changed. SourceFile class found (reused and refactored). WithAfterSourceFileData class added.

Minor: refactoring
Using EditorSourceFileData after cherry-picking.
Activating Kotlin UI plugin on workbench startup.