Instead of the paradigm of generating database files, just generate a folder with the visualization

[fedarko]

The current way is somewhat precarious in that, all of a sudden, there's a version mismatch between the JS interface and the input .db file -- we need to always be cautious that the user's db file isn't "too old" or "too new" for the JS code, which makes developing this kinda frustrating.

The simplest solution I can see is going with the visualization paradigm used by most of the QIIME 2 software, where the python code generates the HTML (with the data pre-baked into there). Since in most cases the data is much larger than any of the surrounding HTML code, this isn't an efficiency problem or anything. It also means we can avoid dealing with SQLite / sql.js, which will make testing a ton easier.

Ditching the SQLite stuff will simplify a ton of the JS code, and also probably make the app more responsive anyway (as I recall the SQLite databases aren't compressed or anything, so I don't think there are any significant advantages to just storing stuff in JSON).

[fedarko]

(FYI this should be closed when the splitup branch is merged in)