Duplicate Tabs Closer per matetoes

NOTE: this is a fork of the original Duplicate Tabs Closer with one minor change: the addition of the Alt+Shift+D shortcut (see the bottom of the description).

★ "On duplicate tab detected" options:
- Close tab automatically: automatically closes the detected duplicate tab.
- Do nothing: monitor tabs and update the badge icon to indicate the number of duplicate tabs detected.

★ On remaining tab options (used with "Close tab automatically):
- Do nothing (default): nothing is done after the duplicate tab is closed.
- Activate: once the duplicate tab is closed, the remaining tab is activated.
- Apply opening tab behavior: once the duplicate tab is closed, depending on the default tab behavior, the remaining tab will be moved to the position of the closed tab and activated if needed.

★ Whitelist (used with "Close tab automatically):
List of urls to not close automatically.
Duplicate tabs detected will be notified in badge.
Wildcards is supported.

★ "Priority" options (used with "Close tab automatically" mode and "Close all duplicate tabs" button):
- Keep older tab (default): Keep the already existing tab.
- Keep newer tab: Keep the newer tab.
- Keep tab with https (default on): Ignore the scheme part during comparison and keep the tab with the https scheme.
- Keep pinned tab (default on): Keep the pinned tab.

★ Filters options:
- Ignore hash part in URL (default off): for instance https://addons.vaultpit.io/en-US/firefox/addon/duplicate-tabs-closer/#detail-relnotes and https://addons.vaultpit.io/en-US/firefox/addon/duplicate-tabs-closer will be considered as the same URL.
- Ignore search part in URL (default off): for instance https://addons.vaultpit.io/en-US/firefox/addon/duplicate-tabs-closer/?src=ss and https://addons.vaultpit.io/en-US/firefox/addon/duplicate-tabs-closer will be considered as the same URL.
- Ignore path part in URL (default off): for instance https://addons.vaultpit.io/en-US/developers and https://addons.vaultpit.io/en-US/firefox/addon/duplicate-tabs-closer will be considered as the same URL.
- Compare with tab title (default off): If the URL doesn't match then compare using the tab title.

★ Scope options:
- Active window (default): only closes/displays duplicate tabs that belong to a same window.
- All window: closes/displays duplicate tabs for all windows.

★ Hotkey:
- Alt+Shift+W to close all duplicate tabs
- Alt+Shift+D to toggle auto-closing of duplicate tabs