Write the "About" page

[JoshKarpel]

As a first draft, we can probably mostly just pull text from other places and drop it here.

• We should have a little cartoon flowchart of the whole process.
• Keep all the descriptions of what the service is here; leave it out of the forms/instructions.

[JoshKarpel]

Given the discussion we just had with Scott, here are some things that should definitely be covered on the About page, maybe in a "requirements" or "assumptions" section:

• You need an Ubuntu 18 machine.
• It needs to be consistently online.
• Your data storage needs to be connected to the machine at all times.