brewkit.rb changes ENV destructively, so lets not do that everytime a formula
is required. Now it's possible for other tools to require a formula
description without worrying about side-effects.
I removed the gnu prefix from libidn and libunistring and I apologise because
I know I made it look like you should add this prefix on previous commits.
We add it when:
1. OS X has a non gnu equivalent pre-installed
2. The package is commonly called GNU foo, eg. GNU Go is not referred to as
just 'Go'
I removed the core suffix from clucene as if anyone ever wants more than just
clucene teh additions should be added as variants to the clucene formula.
Otherwise first class formula, 0xffea noticed all the extra things I usually
do in cherry-picks.
