STORYQ-2 Refactor

[tealefristoe]

JIra story: https://concord-consortium.atlassian.net/browse/STORYQ-2

This is a major refactor of StoryQ. I spent several days diving deep into the code, cleaning things up as I encountered them. There are many changes, many of which I won't include in this write up. But here are the high level objectives and changes:

• Cleaned up typing.
  • Removed almost all any types from the codebase. There are a few exceptions to this that I didn't have time to fix, mostly related to codap-helper.ts and CodapInterface.ts and a few .js files.
  • Many of the previous anys were related to codap API requests and responses. I added codap-api-types.ts to address these. There must be a better way! If we don't already have one, we should try to release a library with API types.
  • I also included slate in the plugin, just to access its basic types.
  • I tried cleaning up places where things were typed as object or things like { [index: string]: string} were used, but it's very possible I missed some.
• Made stores singletons.
  • Previously, these were being passed around as props, and then sometimes saved as class variables. But there was no need to do this, and using singletons greatly simplifies the code.
• Removed a few import cycles.
• Converted several class components to functional components.
• Removed synthetic events from UI components.
  • Was there a good reason to use these events?
• Added and used actions when modifying mobx observable class variables.
• Tried to unify style, which is probably the vast majority of changes in this PR.
  • Added semicolons to the ends of lines.
  • Consistent spacing around ifs, objects, imports, etc.
  • More consistent line breaks.
  • Simplified variable naming in some cases.

[scytacki]

Looks great to me.
I left a couple of comments that you can take or leave.