More alteregos possible actions, vote, flag, etc.

More alteregos possible actions, vote, flag, etc.
Edit action can match the same ego as the ask, answer or comment, or match the original author.
Better help in the ego manager.
All the users can be allowed to have egos, and not only moderators.
The dropdown for alteregos will not show any user if there isn't prefered egos.

git-svn-id: http://svn.osqa.net/svnroot/osqa/trunk@579 0cfe37f9-358a-4d5e-be75-b63607b5c754