Add basic reading support for OWS Capabilities document.
Remove commented code
Fix syntax and private functions return values for OWS format
Rename ol.format.OWSCapabilities to ol.format.OWS
More syntax fix for OWS format
Hit detection skips layers in invisible groups
Merge pull request #1863 from htulipe/ows-capabilities

Add basic reading support for OWS Capabilities documents.
Merge pull request #1943 from elemoine/ht

Hit detection skips layers in invisible groups
Do not return as handled unless a geometry was modified

With this change, it is more straightforward to determine
whether an event is considered as handled, which results in the
removal of the modifiable_ and lastVertexCoordinate_ states.
Instead, we only need to know whether we're on a real vertex or
a virtual one. For that a new snappedToVertex_ flag is
introduced.

To stop a click after vertex deletion from triggering a feature
selection, vertex deletion is now triggered by a configurable
event condition, which defaults to singleclick (same as in the
select interaction) with no modifier keys.
Use the pixelTolerance to determine whether to snap to a vertex
Better documentation for the singleclick condition
Add missing goog.requires; fix types and a typo
Initialize snappedToVertex_
Merge pull request #1914 from ahocevar/modify-event-propagation

Modify interaction breaks mouse wheel zoom
Provide a reference to the layer
Provide layer states array in frame state
Remove layers array from frame state
Make getLayerStatesArray return an array of layer states