Manually input qualitative assessments per farm location

[jgaehring]

While we try to focus on the simplest indicators of crop health, without yet requiring a server to relay these assessments to the dashboard over the network, we want to enable a way for the user to manually enter assessments that may have been received verbally or by email or text.

For now, this can just be a strict qualitative (:red_circle: :yellow_circle: :green_circle:) assessment for each farm location as a whole, before we try to focus these assessments on more specific locations or crops on each farm, and even before we work out how to decrement the status (ie, from :green_circle: to :red_circle:) over time.

If we want to stay super targeted about this, too, we don't need to worry about persisting the assessments either, but if it's easy enough to just do this with a JSON or YAML or CSV file for now, we may as well just so we have a fully closed circuit on this functionality.

[jgaehring]

I've renamed the second milestone to "1.0.0-alpha.1: Track status by farm" and added this issue to it, because I think it and #6 represent the furthest extent of work we need to complete to accomplish that milestone, as summed up in the description there:

Create a working version of the Early Warning System that reflects the rudimentary functionality represented in the mockup (see #3): that is, record when each farm last reported in, what their status was at that time of reporting, and using a very simple algorithm to depreciate that status over time, what their status is currently.

I've also removed #12 and #13 from the milestone, because they are enhancements that fall well outside the scope of that basic description. The location on each farm and specific planting of a crop are not even displayed in that mockup and aren't strictly required to render a qualitative assessment for the farm as a whole. In other words, if the manager asks a farmer, "How's it going?" and they answer "Going great!", "Meh..." or "Help!!!", gut-checks like that can be recorded and updated over time.

Haha, just thinking now, we could replace 🟢 🟡 🔴 with 😎 😐 😭 to make the subjectivity of these assessments more pronounced.