Added GET_MESSAGE_LENGTH_FROM_TX_IN_A
and PUT_PARTIAL_MESSAGE_FROM_TX_IN_A_INTO_B.
Replaced AT-1.3.4 with version including bug-fix for off-by-one
data address bounds checking.
Moved long-from-bytes method to BitTwiddling class.
Renamed some methods to make it more obvious they work with
little/big endian data.