Issue #1459606 by haiiro.shimeji, tmsimont, rjay: Backport from D7 to use Google maps API V3 for D6 6.x-2.x-dev.

Fix #582934, patch by me, rerolled by pivica and hutch: PHP 5.3 compatibility for hook_gmap(). (Manual backport)

* 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

Fix #676108. Original patch by greenSkin, heavily modified by me to hopefully maximize compatibility.

In theory, this should work in both keys_api and keys now.
(cherry picked from commit 2831abcbe55a2b60dbeaeb52e895d0877ef20615)

(cherry picked from commit 62cb91318ddbf045a98b55bd02682b0320cf0ccc)

Fix #155104 by Scott Falconer: Add "Zoom to cluster area" support.

Allow falling back to the default Clusterer marker if desired.

Allow entering larger numbers in some marker manager settings.

Allow choosing between the original and the new "zoom to marker area" behavior on Clusterer.

* Remove references to mousewheel.js, clean up variable.
* Add support for Continuous Zoom, enabled by default.
* Add behavior flag for disabling Continuous Zoom.
* Remove workaround from may 2007 (rev 1.1.2.15) that was causing zooming problems.

Remove the markerdata hack.
Add a marker file generator and fix markers once and for all.
Add a button to the settings page to regenerate the marker cache.

Make a slight change to how gmap element processing works. This should reduce warnings.
Add some tests.