Adds Username element to config.

- Adds new regexes for better config validation.
- Reorders the config elements.
- Removes useless port validation.
Makes small adjustments to inet package.

- Adds a better package comment.
- Makes use of an unused constant.
Makes new Sender interface.
Integrates new Sender with Dispatch.

- Adds sender parameter to Dispatch to allow things that are dispatching
  to provider a writeable object to the reciever of the event.
- Revises current tests and code to include the Sender interface.
- Adds tests to test Sender.
Finishes bringing placeholder into the bot package

- Finishes consuming the configuration to make a bot.
- Adds many new forward facing API's to wrap the interactions with the
  bot. Connect, Start, WaitForShutdown etc.
- Creates a CoreHandler to handle mission critical events such as ping
  etc.
Updates placeholder example and readme.

- Changes placeholder to use the new APIs.
- Updates the readme to reflect a more current version of the bot.