Checkin Controller Polish

Closes #21
Parent #70 (Merge Dependent)
    
- Adds Venue data source for table views
- Refactors Check In controller
- Adds title, new labels, and table view to xib for checkin controller
- Tweaks to VBWelcomController layout
- Adds custom table cell for displaying venues
- Adds caching policy for user count queries
- Adds custom data source for the venue table view
- Moves AppDelegate to the Delegates folder
- Adds custom delegate for the venue table view
- Adds checkmark asset to project
- Adds separator color for UI Table Views
- Adds indeterminate progress indicator for VBHUD
- Adds done indicator for VBHUD
- Balances transition calls in VBRootController
- Increases limit to 50 on Foursquare venue search query
- Adds Venue Table View Cell