Change mammo and fluoro filter lists to use named fields

[Ed McDonagh]

When converting CT to use Celery, the filter fields were named to stop having to quote the whole path into the correct field in the database. Repeat for fluoro and mammo.

Will need to change code in home.html template too.

[Ed McDonagh]

Changed filter names for fluoro and tested. Refs #96.

→ <<cset 18cba2d1fd81>>

[Ed McDonagh]

Changed mammography to use the short database field names, changed home template to suit. Also changed the field names listed for filtering on which hadn't been done for fluoro. Tested and working. Fixes #96.

→ <<cset 6a7085f82cac>>

[Ed McDonagh]

Merge branch ref issue #96 back into develop.

→ <<cset 4346c84b4615>>