outdated doc string copies in the README

[nsajko]

PRs #35 and #39 failed to update the doc string copies in the README. They need to either:

1. be updated or
2. deleted from the README as redundant, as the doc strings should already be included in the autogenerated JuliaHub docs

[ChrisRackauckas]

We should delete them from the readme and just make a real doc.

[0x0f0f0f]

Forgot maketerm. Makes sense to make a real doc.

[0x0f0f0f]

@ChrisRackauckas @nsajko Made #42

[0x0f0f0f]

https://juliasymbolics.github.io/TermInterface.jl/dev/