[Revert]View of the show.html of mall

Revert to the original view of the show.html of the Mall
[Update] View of the show.html of the mall

The view of the Mall's show.html is updated. It will return a blank page is the specific id of the mall is not found.
[Update] mall controller. view and test update

The mall controller is modified to handle the multiple beacon issues and fixing some errors on JSON.

The view and test are modified to suit the modification of malls controller.
[Update] New function is added in application_helper

The application_helper module provides a function to determine image size character 's', 'm', 'l'
Merge remote-tracking branch 'origin/develop' into develop