Added file rename functionality

- Added promise helpers for testing
- Refactored filename prompt to be reusable
- Added move file to ramlRepository and mockFileSystem
- removed dead code in ramlRepository's RamlFile
Merge branch 'file_browser_bar' into features/rename-file-submenu-60342436

Conflicts:
	app/scripts/services/mock-file-system.js
	test/spec/mock-file-system.js
Update ramlRepository mock.
Merge branch 'features/rename-file-submenu-60342436' into file_browser_bar