initial take on re-working layout builder display to align with other templates
cleaned up exhibit list and table view displays
Create abstract base freemix.exhibit.models.DataTransaction to be used for asynchronous data transformation and augmentation. Create viewshare.apps.upload.models.UploadTransaction to handle transformations with Akara.
Create freemix.exhibit.models.ExhibitProperty and Property Data models asyncronously.

Create data migrations for freemix.exhibit.models.DataTransaction and
upload.models.UploadTransaction.