docs + clean up pagination code + a bunch of minor changes

[jrevels]

This is another PR that's crammed with way too much stuff - apologies again. I promise I'll be more orderly moving forward, I just really want to get this merged so we can finally tag a new version.

This PR:

• provides documentation for basically every user-facing part of the package
• simplifies the pagination code, and causes paginated methods to return page metadata so that the user can more easily configure subsequent calls (this is explained in the new docs if you want to read more about it)
• adds a few more REST methods (mainly comment-related functionality)
• removes BasicAuth, which didn't work for authentication in the first place

As for bumping the version number after this PR is merged, I'm not sure whether I should raise the major number or the minor number. There are obviously a bunch of breaking changes since the previous version of the package, and the design has been altered quite a bit.

[WestleyArgentum]

Wow, haven't looked super deep, but this seems like really good stuff.

Re versioning: I'd vote for bumping the major version.

Thanks for putting all this time in, really impressive work.