Consider adding new routes to add/update features

[mfgumban]

Related to MarkLogic ArcGIS Pro Addin:

• The addin currently connects to both Koop and MarkLogic servers, the former for features while the latter for adding/updating feature layers, acting as a sort of "saved search" mechanism.
• Requiring both servers to be accessible might be an issue for IT for many reasons, such as security policies.
• It would be better if the addin just connects using a single entry point (Koop). This would mean adding new routes that conform to the GeoServices spec, such as "FeatureServer/:layer/addFeature", which the addin could potentially use.

[jkerr5]

This was implemented in release 1.1.2.