Webgl immediate implementation for points

Internally uses a replay group to share code.

Modifies the dynamic data example to use PointGeometry
and Feature in addition to MultiPoint.
More lenient Immediate geometry collection rendering

Render geometry collection elements with a valid renderer inspite of
throwing an assertion error. Allows support of hierarchies of points.
More lenient webgl Immediate drawing of a feature.

Remove assert to handle drawing features with supported geometries.
Removing webgl Immediate delegation code for drawing text