Set non-zero exit code on test failure.
Set non-zero exit code on test failure.

This facilitates programmatically checking if a test run failed. This is
handy for automation, bisecting, etc.

rustemferreira/tern,marijnh/tern,mcanthony/tern,cdosborn/tern,fileability/tern,emallson/tern,MarcelGerber/tern,cloud9ide/tern,othree/tern,marijnh/tern,albertinad/tern,messfairy/tern,Icenium/tern,fileability/tern,neoclide/tern,marijnh/tern,cdosborn/tern,mcanthony/tern,emallson/tern,jgiles/tern,messfairy/tern,Icenium/tern,adrianton3/tern,talyian/tern,emacsmirror/tern,jgiles/tern,talyian/tern,rustemferreira/tern,neoclide/tern,rustemferreira/tern,othree/tern,emacsmirror/tern,anandthakker/tern,jgiles/tern,mcanthony/tern,cdosborn/tern,talyian/tern,adrianton3/tern,albertinad/tern,ternjs/tern,dorellang/tern,albertinad/tern,fileability/tern,adrianton3/tern,MarcelGerber/tern,eranif/tern,anandthakker/tern,angelozerr/tern,emallson/tern,MarcelGerber/tern,neoclide/tern,messfairy/tern,dorellang/tern,cloud9ide/tern,ternjs/tern,angelozerr/tern,Icenium/tern,eranif/tern,eranif/tern,anandthakker/tern,emacsmirror/tern,dorellang/tern,othree/tern,ternjs/tern