BUILD: Do not specify path to "true"

true is located at /usr/bin/true under OS X while on most *nix systems
it’s located at a /bin/true. Searching the PATH for true should work on
all systems.
BUILD: Correct date flags for BSD date

BSD date does not recognise --utc however -u is accepted by both BSD
and GNU date.
DOCS: Add Daniel Maloney to the contributors list