refactor: grunt, tests, less code

Main changes:

1. Rename agular module from `hoodieModule` to `hoodie` - this is more conventional angular.
1. Add hoodieProvider, with function hoodieProvider.url, and service hoodie which just returns naked hoodie instance
1. Factor out most of the work for wrapping angular things into utility functions
1. Split up source into multiple files, add tests with access to the helper functions
1. Create grunt task to concat files and wrap them with Hoodie.extend()
1. Add tests for util functions
1. Add TODOs for tests for hoodieArray, hoodieStore, and hoodieAccount
1. In package.json, export only the main file

README is updated with dev instructions, and slightly modded documentation.