Show information about performed refactorings in deleted/added files

[onewhl]

Currently, plugin doesn't show the toggle in code diff in case of removed/added files.
For example, if a method was moved to a new file, the plugin doesn't show any information about it in code diff.

Test for Move Method, Extract Method, Extract Class.

[anchouls]

#103

[onewhl]

@anchouls please check if it works fro Arend project, commit c0ff902179c002d0c2bc57f809f166946e65e8d2.
It seems it doesn't show a toggle in new file for Move and Rename Class refactoring.