TinyCBOR release 0.4.2

This is a bugfix release. Important bugs fixed in this release:
 - Fixed builds against a static cJSON
 - Fixed MSVC builds
 - Fixed builds on freestanding C implementation (no FILE* API)
 - Fixed the return value of cbor_encoder_close_container when a previous OOM
   condition had been detected
 - Fixed the build in strict C89 mode (no C99 extensions)

Signed-off-by: Thiago Macieira <thiago.macieira@intel.com>