Ref #61, updating Admin Guide with new and revised text, adjusted formatting.
Ref #61, updated admin guide header page
Ref #61 Fixed image reference in monitoringthecluster.rst.  Fixed id references on nodestates.rst.
Merge 'gh37' into 3.x
Merge branch 'gh40' into 3.x
Merge galera-3.x upto   dc99c7a4c6c5eac15cd3bf7fb1afe867ed3848af