Don't build the c extension for Heroku or JRuby
Don't build the c extension for Heroku or JRuby

boyang-li/oboe-ruby,boyang-li/oboe-ruby,tlunter/oboe-ruby,appneta/ruby-traceview,appneta/ruby-traceview,tlunter/oboe-ruby,tlunter/oboe-ruby,boyang-li/oboe-ruby,boyang-li/oboe-ruby,appneta/ruby-traceview,tlunter/oboe-ruby,appneta/ruby-traceview