* enhances rendering of tables
* enhances rendering of filter section
* reorganizes table filter codes into konova/filters/ folder and splits into mixins and table_filters
* refactors XYTableFilter classes to hold query_filter and checkbox_filter which are separate instances of django_filter.FilterSets
* improves render ability for frontend
* refactors table filters by introducing AbstractTableFilter, GeoReferencedTableFilterMixin, ShareableTableFilterMixin and RecordableTableFilterMixin
* adds full filter functionality
* refactors TableFilter inheritances for all objects
* adds UserActionLogEntry model to user/models.py
* wraps user and timestamp info
* can be extended for more information in the future
* refactors all filtering and accessing on values
* refactors templates/table.html into templates/generic_index.html
* adds DummyFilterInput as do-not-render-widget
* hardens combination of q filter and other filters on index view rendering