Initial commit.
Update CMakeLists
Add CMake modules for detecting ANSI C headers.

Files from: https://code.google.com/p/libarchive/source/browse/build/
cmake/?name=release-2.7
Update CMakeLists.

Add header and function config defines to CMake.
Disable JavaGenerator in protoc.
Fix #include directives.
Remove debug message from CMake
Enable builds without thread safety.

Allow builds if no threading library is found and user specifies
options GOOGLE_PROTOBUF_NO_THREAD SAFETY.
Replace snprintf to sprintf.

Use sprinf and vsprintf instead of snprintf and vsnprintf due to
toolchain.