PointStream supports PointFeatureCollection.getAltUnit()
* Recompiled pointStream.proto using Protobuf 2.6.0. Updated the maven and gradle dependency.
* Fixed some bugs in ProtobufPointFeatureMaker wrt missing values.
* Improved PointStreamTest. It now round-trip tests our point dataset examples in TestDir.cdmLocalTestDataDir.
* Finished PointFeatureCollection comparison in PointTestUtil.