Only show proposal tags if they exist
Only show proposal tags if they exist

Fixes #28

kgrz/cfp-app,jmccartie/cfp-app,emberjs/cfp-app,jmccartie/cfp-app,rubycentral/cfp-app,malprax/demoConf,ruby-no-kai/cfp-app,malprax/demoConf,katorie/cfp-app,katorie/cfp-app,reinteractive/rails-conf-2015-cfp-app,jmccartie/cfp-app,reinteractive/rails-conf-2015-cfp-app,emberjs/cfp-app,ruby-no-kai/cfp-app,malprax/demoConf,rubycentral/cfp-app,ruby-no-kai/cfp-app,reinteractive/rails-conf-2015-cfp-app,jsis/cfp.jsconf.is,katorie/cfp-app,kgrz/cfp-app,kgrz/cfp-app,jsis/cfp.jsconf.is,emberjs/cfp-app,jsis/cfp.jsconf.is,rubycentral/cfp-app