Add election picker with custom MMPickerView source

Added MMPickerView as separate folder w/ MIT License since
original repo appears dead and fixes were necessary to use
multiple pickers on one controller.

TODO:
Cleanup project directories/groups
Remove UserAddress from Election properties
Rename Election class to UserElection

Done so that UserElection can be split with Election,
allowing for a static list of Elections as a model collection.
Merge pull request #112 from CloudNiner/feature/election-picker

Election Picker Part One