Fixed issue where layers with a min level wouldn't get traversed into in CacheSeed.
Applied same isKeyInRange check to the TMSPackager.
Merge branch 'master' of https://github.com/gwaldron/osgearth
Merge branch 'master' of https://github.com/gwaldron/osgearth
Added FastDXT ImageProcessor
Added fastdxt option to texture_compression mode.
Updated docs to reference fastdxt
Merge branch 'master' of https://github.com/gwaldron/osgearth
Merge branch 'topic-fastdxt'