Mastodonplus.py/DEVELOPMENT.md

Here's some general stuff to keep in mind, and some work that needs to be done

• Mastodon.py tries to work for python2 as well as python3, so avoid things like annotations, use requests over urllib, et cetera.

• Current TODOs:

  • Testing - test 2.3 stuff and verify it works: TODO: media updating
  • 2.4 support:
    • Document and add tests for webpush