Updated to use Connext DDS Java API

Removed code and files that uses the Connext DDS C++ API via JNI, and
modified the code to use the Connext DDS Java API.
Corrected README notes regarding adding shared libs to project.

Corrected methodology for adding native shared libs to project for
including in apk.  Added .gitinores to automatically ignore files that
should not be in respository.