Develop

* HTML indentation cleanup
* View changed to support returning subsets for each facility rather than the first 500 datasets for all facilities
* View shows the number of files in each dataset and total dataset size
* Empty datasets are flagged in red
* Links added to the experiment that each dataset belongs to
* Bugs fixed for viewing datasets grouped by instrument and user (please verify on the synchrotron test data)
* Data loading animation added
* "Load more" button added