Add prototype implement of subtitle shortcuts UI.

Improvement of storing function code structure.
Add prototype implement of subtitle shortcuts Function.

Improvement of storing function code structure.
Add grid layout for prototype implement of subtitle shortcuts UI.
Add subtitle shortcuts UI.
Add subtitle shortcuts function.
Add grif layput style for subtitle shortcuts.
Add shortcuts to title and subtitle input in edit UI.
Add shortcuts to title and subtitle input in edit UI.
Delete useless commented out.
Merge pull request #6 from takashikobayashi/V0.4

V0.4