Updated CMakeLists.txt to use the new FlatBuffers build rules.
Updated CMakeLists.txt to use the new FlatBuffers build rules.

Also, no longer copying text schemas to the assets folder.

Change-Id: I7b9190c717786f0aef6f34665b403df25e21f386
Tested: Linux desktop build completed.

google/fplbase,google/fplbase,google/fplbase,google/fplbase