Allow Importing and Exporting Tab(s)
Added a hidden action to open tab group in new window
UI Fixes
Bug Fixes

* seamlessly switch tabs using popup window
* fix alignment issues with lengthy titles in tab manager window

* fix spawning of wrong index in create tab
* filter taburei manager tab when collapsing
* add option to selectively collapse tabs
* show group properities including number of tabs and group name
* allow changing names of groups

Update icons and favicon
Move tabs to different group by dragging
Use event delegation
Bump version to v0.6.0 due to major rewrite
Spawn a new tab instead of hyperlinks
Modify styles and add tooltip text
Major README overhaul

* packaged without polyfill for firefox
* updated icons and added favico

- Much more intuitive UI
- See a list of all your opened tabs in one place.
- Collapse and save all your tabs on one click.
- Group tabs and manage them in one place.
- Tabs retain the prior state like pinned, reader mode and containers.