Pin tabs

[Defman21]

The idea:

• Pinned tabs will be restored after closing Komodo.
• Pinned tabs could execute any command when restoring itself (set by user). [could be empty]
• Pinned tabs will keep their name.

Mockup:

• A menuitem under menupopup for tabs to pin them
• A menuitem under menupopup for tabs to edit their command

Implementation:

• Pinned tabs will be stored in JSON format in ko/prefs => (string) komodo_terminal_pinned_tabs

{
    "tabs": [
        [
            {
                "label": "Tab => (string) label",
                "command": "Tab => (string | null) command"
            }
        ], ...
    ]
}