Ref #61 Updates to performance.rst, reorganization of configurationtips.rst
Ref #75.  Documented state transfer methods used in automatic donor selection.
Ref #87 Fixes to MySQL installation pages.
Merge branch 'gh92' inti 3.x
Merge galera-3.x upto c5353b1031ca88414430035e4b39f69a1faec7cf