Removed extra comma

Fixed Error trying to parse file: Trailing comma before closing bracket in E:\Sublime_Text_x64\Data\Packages\PlainNotes\Main.sublime-menu:54:89
Merge pull request #11 from serbanghita/master

Removed extra comma
Merge pull request #12 from fk128/master

index now displays only files listed in settings
added option to choose save file ext in settings.
Merge branch 'master' of https://github.com/aziz/PlainNotes
updated README