The 'layercount' attribute was not used anyway and the calculated number could already be outdated when loading the project file again due to changes to embedded projects.
* layerFilterExpression
Return an additional filter, used in
WMS/GetMap, WMS/GetFeatureInfo, WFS/GetFeature to filter the features
* layerFilterSubsetString
Return an additional the subset string (typically SQL) filter.
Faster than the layerFilterExpression but not supported on all the
type of layer
* layerPermissions
Change the rights on the layer per user (known by the plugin)
Concern rights: publish, insert, update, delete.
Mostly used in WFS/Transaction, and the publish in all requests.
* authorizedLayerAttributes
Be able to show some attributes only for a subset of user
Used in: WMS/GetFeatureInfo, WFS/GetFeature
* allowToEdit
Be able to don't allow to edit a particular feature, in our case base
on the Geometry
Used in: WFS/Transaction
* cacheKey
Cache key to used to create the capabilities cache, "" for no cache,
shouldn't contains any "-", default to ""
