SplitFeature - new widget

[adube]

Add a new widget that use the OpenLayers.Control.SplitFeature control in order to split features on the map. The widget should :

• use 'featureserver' service for the moment, but could easilly be adapted to 'wfs' later
• use the existing vector layer linked to the resource features it has to split
• not take care of editing the feature attributes after splitting.
• have the possibility to allow feature attribute edition only via custom methods specified as resource options.
• open a popup after splitting a feature to validate the changes (thus saving them) or cancel them (refresh the layer).
• toggle the vector layer ON on activate and OFF on deactivate

possible other enhancements

• allow the edition of the geometry after splitting
• use the topology rules when editing the geometry

[adube]

In order to have the 'split' in the same stack as the editing widgets, we'll add it in the 'editfeature' directory but it won't extend or use any of the other widgets code except the goEditFeatureActions variable.

[adube]

The OpenLayers.Control.SplitFeature control doesn't support splitting polygons. A temp override will be necessary to fix this issue until OpenLayers is fixed.

[adube]

r1096, r1097, featuring :

• a new editfeature_split widget
• documentation
• support for all config drivers
• a sample
• polygon supported
• layer toggled ON and OFF on control activation/deactivation
• window opened after split (must be created manually)
• uses the existing vector layer (using featureserver service)

The rest of the possible enhancements should pumped to new tickets.

[adube]

r1099, fixing the missing 'needLayer' for PGSQLMapContextConfig driver

[adube]

r1100, making the precision lower to detect that a point intersects a line.

[adube]

r1100, featuring : new 'splitFeatures' array as private property used to push the original and split features

[adube]

typo : r1101

[adube]

r1103, fix to allow the use of the commit method.