cf8d1b0387
`build_process` has been around a long time but it's become a very large,
unwieldy method. It's hard to work with because it has a lot of local
variables that need to persist across all of the code.
- [x] To address this, convert it its own `BuildInfoProcess` class.
- [x] Start breaking the method apart by factoring out the main
installation logic into its own function.