gitstats: Modified test-lib.sh to use ~/code/git as git dir.
Because we are not running from inside a git.git repository
but the test harness does expect this, point everything at
a real git.git repository under ~/code/git.
This is ofcourse setup dependant and a more elegant
solution will have to be introduced later on.
This change also adds my personal modifications to
test-lib.sh which make it output additional information
about how many testcases passed/failed so for easy
data-mining later on.