Fixed editor tag field handling of comma key on international keyboards
Fixed editor tag field handling of comma key on international keyboards

fixes #4356
- Added new keyPress event handler to identify keys by character instead of key
- Removed code for handling comma key from keyDown event handler

airycanon/Ghost-Admin,kevinansfield/Ghost-Admin,dbalders/Ghost-Admin,JohnONolan/Ghost-Admin,TryGhost/Ghost-Admin,TryGhost/Ghost-Admin,acburdine/Ghost-Admin,JohnONolan/Ghost-Admin,kevinansfield/Ghost-Admin,airycanon/Ghost-Admin,acburdine/Ghost-Admin,dbalders/Ghost-Admin