Original commits were for #679804.

  * Add Google Bar to search on map
  * Add option for a marker tooltip field on gmap views
  * Add option to highlight markers on mouse rollover event
  * Add option to center Gmap on marker of node passed as argument in view
  * Add option to highlight markers of node passed as argument in view

Also, fix a warning caused by neglecting to give the row plugin a chance to query.
Additionally, ensure that views knows we are capable of doing grouping.
The fix is based on the changes presented in #619884 for views.

Hopefully fix #371134: warning: Invalid argument supplied for foreach()...gmap_plugin_style_gmap.inc on line 172.

Add the ability to base gmap views off of arbitrary fields. Also add a way to specify the marker using a field.

As a side effect, this means that using a location_cck relationship will now do the right thing for a gmap view.