Tidying up the rake file
Ignoring contents of tmp directory
Adding dummy persistence layer for some testing
Adding a data structure to define the interface

This is a thought experiment, as I'm trying to codify what an Activity
is (or at least what is required for one to be made)

@TODO - There is perhaps a better means of inferring this contract
Adding basic behavior of the Satchel

Allow for the registry of methods
Adding explicit require for classes