ALLJOYN-2381 Remove out-of-date test program uarttest1.c
ALLJOYN-2386: ValidateHeader return type conversion error
ALLJOYN-2387 Update MutterTest to pass hdr checks

ALLJOYN-2383 added stricter header validation checks, rejecting
bad messages that miss some fields. The mutter test program doesn't
connect to a daemon and has an uninitialized uniqueName. This casues
the sender field check (and subsequently the test itself) to fail.

Fix.: Initialize the uniqueName to a dummy value to ensure that
      test program is able to run.

Change-Id: If7660c86663ca5cf3f4fdfb5346801d0c0d3d544