Update README.md
Update README.md
Bumped version to 0.5 for next feature set, added stable branch

Signed-off-by: Ozan Turgut <ozanturgut@gmail.com>
Merge branch 'master' of github.com:ozanturgut/queen
Reverted version to 0.4.0

Signed-off-by: Ozan Turgut <ozanturgut@gmail.com>