Improve category based date filters

[j9recurses]

Improve category based date filters

[jasonlally]

I'll pick this one off.

[jasonlally]

Per conversation with @j9recurses I'll look at popping out duplicative fields for filtering dates. I'll think about this a bit more while I'm in the code, because there may be some simpler ways to handle this like providing just in time context for fields on the filter cards so the user can make informed decisions about which filters to use.

[jasonlally]

I've looked into this and there are a couple of things we can do to address this issue without overcomplicating.

• When years are presented as a categorical variable (as opposed to a date field) - order the drop down list sequentially - in general we'll default to sequential across all filter dropdowns and consider ordering by counts pending user testing
• Process these fields consistently so they show up as group by options as well as filters (this may take a little bit to get right, but we can probably do something for now that's good enough and iterate based on user feedback)

[jasonlally]

Addressed by PR #54