Add puppet 3.1.1 to travis matrix.
Add puppet 3.1.1 to travis matrix.

zapier/puppet-redis,craigcarnell/puppet-redis,craigcarnell/puppet-redis,thomasvandoren/puppet-redis,zapier/puppet-redis,zapier/puppet-redis,tiredpixel/puppet-redis,tiredpixel/puppet-redis,hypernova2002/puppet-redis,hypernova2002/puppet-redis,hypernova2002/puppet-redis,craigcarnell/puppet-redis,tiredpixel/puppet-redis