Add a summary of how to submit a pull request

Also add REP 137 reference.
fixing quotes
releasing smach 1.3.0 to hydro
fixing packages list formatting
Merge pull request #775 from jbohren-forks/master

releasing smach 1.3.0 to hydro
Merge pull request #768 from ros/readme_update

Add a summary of how to submit a pull request
Merge pull request #776 from jbohren-forks/joystick_drivers

releasing joystick_drivers 1.9.10 to groovy and hydro
add more timeouts for groovy and hydro
[hydro] remove version of joystick_drivers since the gbp does not contain a hydro release
re-adding joystick drivers to hydro