Add keyboard shortcuts

[szpak]

Feature description

It would be nice to have be able to perform majority of actions with a keyboard shortcut

Shortcuts status

• [x] Add Task - CTRL-SHIFT-T
• [x] Add Subtask - CTRL-SHIFT-Y
• [x] (Batch) Edit Task(s) - CTRL-SHIFT-E
• [ ] Quick (inline) Edit Task - ``ENTER/F2`?
• [ ] Remove Task(s) - Delete?
• [ ] Complete Task - CTRL-SHIFT-C?
• [x] Batch Add Tasks - CTRL-SHIFT-B
• [ ] Quick Add Task - CTRL-SHIFT-Q?
• [x] Add Note - CTRL-SHIFT-N
• [ ] Remove Note(s) - Delete?
• [ ] Save - CTRL-SHIFT-S
• [ ] Settings - CTRL-SHIFT-??
• [ ] Synchronize - ?
• [x] Close current dialog - ESC

Detailed information

Currently it seems to be not keyboard shortcuts available in the app. For people preferring keyboard over mouse it's a productivity problem.

I don't know Electron, but it seems to be possible to define Local shortcuts within the app: https://electronjs.org/docs/tutorial/keyboard-shortcuts (preferably similar to the old ones if appropriate)

Version and system information

0.2.0-alpha on Fedora 30.

[szpak]

I updated the original issue to cover status of the main keyboard shortcuts and be able to link related issues to that "umbrella task".