Code refactoring and fix issue #11. Thanks to @dvngn
https://github.com/sagitta1618/temporaryTabContainer/pull/13

removing temporary container 5s after the last tab using it is closed.

minimize tab bar shaking on session restore but using tab index to preserve tab order when reloading in new TC.

- (fix) pinned tab now reopen in a new TC as pinned

- last tabs restored from a previous browser session are now opened in a new TC after all TC are erased at session start.

- temporary container are now deleted at every new session start. This allows to keep temporary container around during the same browsing session and makes it perfect to use with tab managing extensions.

- internal code tidying
- fix the remove last TC tab

fix not removing temporary container because of name change 'priv9' to 'TC'

change 'priv9-' to 'TC' for Temporary Container