Add support for Hexagram30 Dice Roller

[oubiwann]

Dev tasks:

• Add top-level roll command
• Add ping subcommand
• Add version subcommand
• Add meta subcommand
• Add arg-parsing support for all types of rolls
• Handle all old CLI usage (see Support all old CLI usage in new gRPC server dice#9)
  • hxgm30 roll <dice-type> (method Roll)- a single roll
  • hxgm30 roll <dice-type> <count>(method RollN) - multiple roles of a single type of dice
  • hxgm30 roll <dice-type> <count> [<dice-type> <count> ...] (method RollVarious) - multiple rolls supporting different types of dice
  • hxgm30 roll meta <dice-type> <count>(method RollNMeta) - multiple rolls of a single type of dice with stats included in the results
  • hxgm30 roll meta <dice-type> <count> [<dice-type> <count> ...] (method RollVariousMeta) - multiple rolls supporting different types of dice with stats included in the results

[oubiwann]

Hrm, I think this work is done, now; need to double-check ...