This documents the outcome of the change in
https://github.com/NixOS/nix/issues/454:
> We can also automatically add parentheses in the generated
> `buildInputs`, so you can type `nix-shell -p "expr"`
> instead of `"(expr").
In particular, drop the "build-" and "gc-" prefixes which are
pointless. So now you can say
nix build --no-sandbox
instead of
nix build --no-build-use-sandbox
"build-max-jobs" and the "-j" option can now be set to "auto" to use
the number of CPUs in the system. (Unlike build-cores, it doesn't use
0 to imply auto-configuration, because a) magic values are a bad idea
in general; b) 0 is a legitimate value used to disable local
building.)
Fixes#1198.
