Terminal tabs improvements

[Yaraslaut]

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Some terminal tab customization and features that would be nice to have

• this issue is much more relevant now https://github.com/contour-terminal/contour/issues/758 and we need to customize this behavior since user might want to open new tab in the same directory
• For every tab show status of the running process, ideally i would like to see indication whether program that i launched is finished or not, for example I wget big file and switched to another tab, i would like to notice when wget is finished
• from @classabbyamp it'd be nice if ShiftToTab{Left,Right} wrapped around (for a window with 3 tabs) 1 -L-> 2 -L-> 3 -L-> 1 -R-> 3 -R-> 2 -R-> 1 -R-> 3