Issue #1928812 by Jerenus | Summit: Fixed Notice: Undefined index: node in gmap_taxonomy_get_instances() (line 269 gmap_taxonomy().module.

Issue #1057922 by Digeridoo, juhaniemi, victoriachan | casaswing: Fixed Proper use of GMap Taxonomy and Node Marker in Views.

It's pretty obviously flawed, but everything is up and running except association.

It doesn't really make much sense under D7 anyway, taxonomy doesn't associate with nodes the way it did before,
it's all field based now.

* Clarify what the first option for the marker does.
* Fix unsetting a marker deliberately
* Fix several bugs with updating marker associations after changing a term.
* Fix SQL error when setting a marker on existing terms.
* Add function to recompute markers after changing a term.

* Delete marker associations properly.
* Join to {node_revisions} properly.
* Handle upgrading from a 5.x version after the changed I just made in that branch.