Fix rpclib code style and misc issues, update RPC unsigned types.

 - Fix code style, add assertions and annotations.
 - Have the rpclib multiplexer code run on the client's executor.
 - Update all unsigned types to match their primitive signed type.

Note: extra care must be taken when decoding primitive RPC types
to be interpreted as unsigned values, e.g. reading an unsigned
short becomes: int unsignedValue = decoder.uint16() & 0xffff;

Change-Id: Ib6dbd0b191f3419d1f65bedfef127aadd86d5dd4
15 files changed