Update .travis.yml
Update .travis.yml

This commit brings .travis.yml up to date with the other puppetlabs
modules. It will cause tests to run on Puppet 2.7 and the latest 3.x
instead of every minor 3 version. This will avoid strange failures
on older puppet versions.

mrobbert/puppetlabs-corosync,fghaas/puppet-corosync,wywygmbh/puppetlabs-corosync,Proteon/puppetlabs-corosync,mkrakowitzer/puppetlabs-corosync,pgotsis/puppet-corosync,gwdg/puppetlabs-corosync,voxpupuli/puppet-corosync,pulecp/puppet-corosync,rdo-puppet-modules/puppetlabs-corosync,redhat-cip/puppetlabs-corosync,fghaas/puppet-corosync,GiooDev/puppetlabs-corosync,tdb/puppet-corosync,fuel-infra/puppet-corosync,mkrakowitzer/puppetlabs-corosync,GiooDev/puppetlabs-corosync,tdb/puppet-corosync,pgotsis/puppet-corosync,wywygmbh/puppetlabs-corosync,rdo-puppet-modules/puppetlabs-corosync,redhat-cip/puppetlabs-corosync,pulecp/puppet-corosync,voxpupuli/puppet-corosync,mrobbert/puppetlabs-corosync,Proteon/puppetlabs-corosync,puppet-community/puppet-corosync,fuel-infra/puppet-corosync,puppet-community/puppet-corosync,gwdg/puppetlabs-corosync