Merge pull request #30 from esc/feature/better_author_list

use git shortlog and .mailmap to remove duplicates

.mailmap

+Richard Hartmann <richih.mailinglist@gmail.com> <richih+github.com@richih.org>

tools/list_AUTHORS

@@ -2,4 +2,4 @@
 
 echo 'Alphabetical list of everyone who ever committed to this repository
 '
-git log --all --format='%an <%ae>' | sort -u -k2
+git shortlog -se --all | cut -f1 --complement | sort -u -k2