suggestions for upgrade.txt file

1. Include the notes on upgrade order and dependencies from http://groups.drupal.org/node/12485#comment-40078 and http://groups.drupal.org/node/12485#comment-40097

2. If you are using the Views module to display nodes on a GMap view, check the appearance of those views after the upgrade. If you find the marker type is not what you expect, use the 'Markers per content type' section on the GMap Location settings page to specify the correct marker for your content types.

[#2 is the only problem I've found after upgrading to the beta1 version. I guess it is a result of an earlier bug being fixed.]