[Azoth Abbrev] Added ShortcutsManager stubs.
[Azoth Abbrev] Aded shortcuts manager for #1763.
[Azoth Abbrev] Handle destroyed chat windows for #1763.
[Azoth Abbrev] Instantiate shortcuts mgr for #1763.
[Azoth Abbrev] Implement IHaveShortcuts for #1763.
[Azoth Abbrev] Handle new tabs, finally closes #1763.