lots of updates to the readme to: improve scientific and technical clarity, reflect all recent changes to the CLI (especially the addition of prepare), reflect all recent changes to our installation, improve explanation of how to handle a few different kinds of data, and expand instructions on contributing and developing
* refactor cli to improve ux and enable easy incorporation of prepare as a subcommand
* switches to use click, which removes some boilerplate and gets us some improved ux for free
* changes the entry point for the cli
* changes the name of the browser option to --open and makes the default false
* add prepare cli
* fix handling of user path
* fixes for linter
* add flags and options for handling obs and var names
* add prepare cli
* fix handling of user path
* fixes for linter
* add flags and options for handling obs and var names
* address review requests
Jeremy Freeman