R1:9ab22e21b305

Allow installs to customize project icons

Summary:
Ref T10010. Ref T5819. General alignment of the stars:

- There were some hacks in Conduit around stripping `fa-...` off icons when reading and writing that I wanted to get rid of.
- We probably have room for a subtitle in the new heavy nav, and using the icon name is a good starting point (and maybe good enough on its own?)
- The project list was real bad looking with redundant tag/names, now it is very slightly less bad looking with non-redundant…