Misc cleanup blocking CC-Release. (urbit#1249)

* Move extraneous stuff out of pkg/urbit/*
* s/urb/herb/g
* Removed some boilerplate for `urbit` builds.
* Build urbit tests and run them in the nix build.

Author: benjamin-tlon

Makefile

@@ -5,13 +5,13 @@ PKGS = minima extrema rusthello prog
 .PHONY: build build-all install release test clean
 
 build:
-	nix-build -A urbit -A urb --no-out-link
+	nix-build -A urbit -A herb --no-out-link
 
 build-all:
 	nix-build --no-out-link
 
 install:
-	nix-env -f . -iA urbit -iA urbit-debug -iA urb
+	nix-env -f . -iA urbit -iA urbit-debug -iA herb
 
 release:
 	sh/release urbit linux32