requirements-extra.txt was missing from pypi source distribution

29b39e6c · Paul McCarthy · 0a6377a7 · 29b39e6c
Commit 29b39e6c authored Feb 09, 2018 by Paul McCarthy 🚵
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -2,6 +2,7 @@ include           LICENSE
 include           COPYRIGHT
 include           requirements.txt
 include           requirements-dev.txt
+include           requirements-extra.txt
 include           pytest.ini
 recursive-include doc      *
 recursive-exclude doc/html *