Fix candidacies tableView.

Now displays candidacies. One can select 2 candidates and the deckViewController will switch from the candidaciesViewController to the tagsViewController.
Add Tags model
Add Tags tableView

- Add Tags tableView
- remove request on tags tableview
- change background to white under tableViews
Display propositions
Allow the selection of multiple candidacies
Merge pull request #1 from pH-k/motion

Motion
Add HUD when loading propositions

- added MBProgressHUD pod
- when a request to fetch propositions is fired up, an HUD appears on the webView (it disappears when the request finishes to load or when the request fails)
Display photos in candidacies tableView

- added AFNetworking library (bubblewrap does not do asynchronous image download)
- added placeholder image (not sure if it works)
Fix placeholder image in candidacies tableView

- fix placeholder image in candidacies tableView
- add a message to the propositionsViewController hud
Merge pull request #2 from pH-k/motion

Motion
Add icons to tags

- add iconURL to tags model
- retrieve icon when loading tags tableView
Logs and formatting
Update gitignore
Update tags tableview
Button with voxe logo
Update rakefile & TestFlight config (without tokens)
Choose election
Simplify election selection
Only display back button when needed
Fix tags table view row height