Write a command-line tool for encoding, decoding, and examining DCCL schemas and messages

Create a command line tool (probably called "dccl") that allows the user to: 1) inspect the size bounds of a given DCCL message; 2) encode a DCCL message to hexadecimal, protobuf binary, or protobuf TextFormat, 3) decode a DCCL message from the same formats. (This tool will replace the existing "analyze_dccl" which only performs item 1.)