`GIT_DIR` support isn't right. Git does not look for `GIT_DIR/.git`;
git-annex does.

Also, to support this scenario, support for core.worktree needs to be added
as well:

	mkdir repo workdir
	git --work-tree=$PWD/workdir --git-dir=$PWD/repo init
	export GIT_DIR=$PWD/repo
	git status
	# ok
	git annex init "new repo"
	# fail

--[[Joey]] 

> [[fixed|done]] --[[Joey]] 
