Fix incorrect gitstats version.

If the VERSION variable was not filled in, gitstats would run
'git rev-parse' on the repository being examined instead of the
gitstats repository.

Signed-off-by: Sven van Haastregt <svhaastr@liacs.nl>

gitstats

 def getversion():
 	global VERSION
 	if VERSION == 0:
-		VERSION = getpipeoutput(["git rev-parse --short %s" % getcommitrange('HEAD')]).split('\n')[0]
+		gitstats_repo = os.path.dirname(os.path.abspath(__file__))
+		VERSION = getpipeoutput(["git --git-dir=%s/.git --work-tree=%s rev-parse --short %s" %
+			(gitstats_repo, gitstats_repo, getcommitrange('HEAD').split('\n')[0])])
 	return VERSION
 
 def getgitversion():