Auto-cache Mapbender's application YAML files

The possible multiple applications YAML files now trigger cache
rebuild in dev mode when changed.
Working applications YAML caching with one single caveat

Cahcing applications YMALs works now by using FileResources
for each one. Therefore adding new YAMLs will not trigger a
cache refresh. Once the cache has been refreshed, they will
be included in the cache dependencies.
wmc functions load remove added
Merge branch 'develop' of github.com:mapbender/mapbender into develop
WmcParser chenged
layertree checked changed
Merge branch 'develop' of github.com:mapbender/mapbender into develop
Merge branch 'develop' into feature/template