Begin documenting the common interface at a high level

[ChrisRackauckas]

No description provided.

[ChrisRackauckas]

@frankschae I'll pull you in for the differentiation section later. First I want to get something merged quickly so we can all collab on different parts (and open bounties)

[codecov]

Codecov Report

Merging #67 (646ffd2) into master (697bd0c) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #67   +/-   ##
=======================================
  Coverage   11.00%   11.00%           
=======================================
  Files          39       39           
  Lines        2852     2852           
=======================================
  Hits          314      314           
  Misses       2538     2538           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 697bd0c...646ffd2. Read the comment docs.

[frankschae]

sounds good. Is this in addition to existing docs or is it intended to replace them?

[ChrisRackauckas]

I think just in addition. The current docs are all differential equation focused. My plan is that every equation package (differential equations, nonlinear systems, optimization, etc.) is documented in such a way that they are complete: a user feels fine using that package in isolation (so NonlinearSolve.jl needs help). But we need to also document at a high level exactly how things relate between the packages. It's more from a design point of view to explain it all to both deep users and potential developers. For example, what is the relationship between sensealg on differential equations and nonlinear solves? That doesn't have a place, but it's important to define what exactly a sensealg is, what it does, that it's universal, and how the arguments should always be defined.