removed stealth from specials not specifically stealth related, and removed last vestige of LRN_RUIN_MOD, and commented out Super Tester Takeover in preunlocked to avoid error messages.

git-svn-id: https://freeorion.svn.sourceforge.net/svnroot/freeorion/trunk@5715 dbd5520b-6a0a-0410-a553-f54834df5b05
Clarified description of BLD_BLACK_HOLE_POW_GEN.

git-svn-id: https://freeorion.svn.sourceforge.net/svnroot/freeorion/trunk@5716 dbd5520b-6a0a-0410-a553-f54834df5b05
- Updated the changelog.

git-svn-id: https://freeorion.svn.sourceforge.net/svnroot/freeorion/trunk@5717 dbd5520b-6a0a-0410-a553-f54834df5b05
Merge remote-tracking branch 'svn-mirror/master'