[TASK] Cleanup and Redesign Upgrade Analysis

* removed unused variables from install.sass
* changes js to move entries from read to unread and the other way around
* add panel colors
* add risk levels
* fix old TER files

Resolves: #80465
Releases: master
Change-Id: I9dd6913c3c99df3e7b59cb7f3ea95b6d05918086
Reviewed-on: https://review.typo3.org/52172


Reviewed-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Tested-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Reviewed-by: Frank Naegler <frank.naegler@typo3.org>
Tested-by: Frank Naegler <frank.naegler@typo3.org>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>
Tested-by: TYPO3com <no-reply@typo3.com>