Do not make 2 builds on Travis for branch + PR
Do not make 2 builds on Travis for branch + PR

* See travis-ci/travis-ci#3340.
* Unfortunately this means we might need an extra PR just to have "try" branch build.

lucaspinto/rubyspec,wied03/rubyspec,yous/rubyspec,yous/rubyspec,sgarciac/spec,kachick/rubyspec,benlovell/rubyspec,BanzaiMan/rubyspec,eregon/rubyspec,kidaa/rubyspec,ruby/rubyspec,sgarciac/spec,kidaa/rubyspec,benlovell/rubyspec,nobu/rubyspec,bl4ckdu5t/rubyspec,lucaspinto/rubyspec,ruby/rubyspec,bl4ckdu5t/rubyspec,wied03/rubyspec,iliabylich/rubyspec,ruby/spec,iliabylich/rubyspec,nobu/rubyspec,eregon/rubyspec,ruby/spec,askl56/rubyspec,jannishuebl/rubyspec,askl56/rubyspec,eregon/rubyspec,wied03/rubyspec,kachick/rubyspec,ruby/spec,nobu/rubyspec,sgarciac/spec,kachick/rubyspec,jannishuebl/rubyspec,BanzaiMan/rubyspec