beta: fix ansi escapes for wmf-beta-autoupdater

* the ANSI escape to reset color was wrong. Fixed it up.
* changed colors scheme entirely
* created entry for level CRITICAL, although it is unused.

Change-Id: I8423bd8e9c072fb8b55622be20b34686e6ca0651
Merge "beta: fix ansi escapes for wmf-beta-autoupdater" into production