Refactoring: use resolve session instead of binding context
KT-5103 No delegated members in Override/Implement

 #KT-5103 Fixed
Remove rest of whitespace on override or implement to insert generated at caret offset
Move caret to generated element and add selection
Refactoring: extract method
Refactoring: rename and make public
Auto insert caret and selection to "after" file
Auto generate "after"-file if it's not present
More tests for generating methods from different caret positions