decoder: support opcodes the encoder produces
decoder: avoid problems with short reads
encoder: fix integer encoding ranges
decoder: add BINGET / LONG_BINGET
encoder: oops, uint16s are little-endian too
Merge pull request #3 from dgryski/more-encoding-decoding-work

A few more small fixes to the encoder and decoder.
decoder: add support for opGet ('g') opcode.
Merge pull request #4 from dgryski/decoder-get

Add support for decoding opGet ('g')