1.0 of non-API Documentation

[ryanmrichard]

This PR is designed to get the documentation into a 1.0 state:

• [x] adds a logo
• [x] updates README.md
• [x] updates dependencies to not use PluginPlay
• [x] adds installation documentation
• [x] refactors existing background, design, and tutorials into release vs. experimental

Once this PR is done, the remaining task for a 1.0 is to go through the API documentation of the release classes and make sure it's up to snuff. That will likely involve changing a lot of files so I'll do that in a separate PR.

[ryanmrichard]

I think this cleans it up enough for the purposes of this PR. For my next PR I'm going to go through the Doxygen that's there and clean that up. In the process of doing that I will tweak the design documents for the chemical system component.

This is r2g.