Fix all the compile warnings generated following adding WARNING_CFLAGS
to all the Makefile.in files.
Fix tests/unit-tests/testdriver failures caused by dtls_prng() return value.
Signed-off-by: Jon Shallow <supjps-libcoap@jpshallow.com>
Add a subdirectory tests/unit-tests for unit tests based on cunit.
The unit tests are run by invoking the executable testdriver or
make check.
Initial unit tests with test vectors for CCM from RFC 3610 are
provided.
Change-Id: I3e8eb0e147ff357f54830e15cfe0346f83a5d28b