Fix physical view in-rack machine ordering

The physical view was not ordering machines in a rack by their rank.  Revert to the behavior of the original Ganglia web interface where this was done.
Don't know how this even worked
Merge pull request #232 from hollowec/physviewfix

Fix physical view in-rack machine ordering
Changed showhosts_levels ordering
Merge pull request #234 from gfosco/showhosts_levels

Changed "Show Hosts Scaled" button indexes