Loading a WMC remove actual layers instead of destroying them
replace layer type by grid based on image for fake backgroundlayer
Fix dependencies
Update GN submodule.
add comment about the image grid layer
Update gn submodule.
Merge pull request #263 from fgravin/mousescroll

mapfishapp: map mousescroll bugfix
Fix for: https://github.com/georchestra/georchestra/issues/266
fixed mapfishapp build by removing OpenLayers/Layer/OSM.js
Update gn submodule.
Update fr.js
Merge remote-tracking branch 'origin/stable'