Cleanup hidl-gen

* Move Parser to its own class.
* Move the utiity functions to GeneratorUtility class.
* Remove snippets.rb (using the make_snippets.py instead).
* Rmove vts_gps.hidl and vts_lights.hidl (both have copy under tests/)

Change-Id: I0bf6d0f8ab3e27d4e10f7a8d79a0a836e87a769c
13 files changed