Now the Build tool needs to define -DHAVE_ZLIB and -DHAVE-PTHREAD rather
than providing a config.h
- Make pbconfig.h a manually written file to handle hash conditions
according to platform related macros.
- Remove #include "config.h" from source code.
- Changed the configure.ac and Makefile.am to pass down the macros.
- Change cmake to pass down the the macros.
Change-Id: I537249d5df8fdeba189706aec436d1ab1104a4dc
Escape characters don't count for string literal size, no need to pre-generate escape string.
Added unit test to touch enormous cpp generated descriptor.
Updated makefile to include enormous_descriptor.proto
Fixed language compatibility error.
