Removed yahoo layer refernce
Update version in geomoose.html in 2.7.
Merge branch 'master' into visible_layers_extension
Add layer remove button on VisibleLayers tab.

Rough implementation
TODO: Turn off GeoMoose layer.
TODO: Use better button icon than down arrow.
Merge branch 'visible_layers_extension' of github.com:geomoose/geomoose-js into visible_layers_extension

Conflicts:
	extensions/VisibleLayers/tab.js