Starting to reinstate and update DXSummaryListFilter. Age gt not currently working. Might continue upgrade to later Django and version 2 of django_filter before attempting to fix. Refs #404, #437 [skip ci] not ready for tests
DX summary filtered page now working with all filters except age with django_filters 1.1, Python 3.6, Django 1.8.
Need to repeat for other modalities, then move onto Django 1.9 I think.
Refs #437, #404 [skip ci] not ready for testing
Not sure why some mam image values are bytes that need decoding before casting to Decimal, others are float or int. Hence try:except:. Also corrected mod_filters test and reverse_lazy. refs #404, #437 [skip ci] - not ready for testing