Refactor downloads in PHP app
Refactor downloads in PHP app

Now download is accessed via GET request and a download action. Also
removed all download logic from the save code (wooo).

knpwrs/jsbin,Hamcha/jsbin,digideskio/jsbin,juliankrispel/jsbin,mcanthony/jsbin,dedalik/jsbin,pandoraui/jsbin,yohanboniface/jsbin,arcseldon/jsbin,saikota/jsbin,knpwrs/jsbin,kirjs/jsbin,fend-classroom/jsbin,vipulnsward/jsbin,filamentgroup/jsbin,IveWong/jsbin,carolineartz/jsbin,dhval/jsbin,eggheadio/jsbin,Hamcha/jsbin,dhval/jsbin,ilyes14/jsbin,AverageMarcus/jsbin,johnmichel/jsbin,jamez14/jsbin,yize/jsbin,carolineartz/jsbin,svacha/jsbin,ctide/jsbin,svacha/jsbin,fgrillo21/NPA-Exam,dedalik/jsbin,kirjs/jsbin,KenPowers/jsbin,jwdallas/jsbin,yize/jsbin,mlucool/jsbin,yohanboniface/jsbin,Freeformers/jsbin,dennishu001/jsbin,jwdallas/jsbin,simonThiele/jsbin,HeroicEric/jsbin,jamez14/jsbin,vipulnsward/jsbin,mingzeke/jsbin,mlucool/jsbin,eggheadio/jsbin,nitaku/jervis,KenPowers/jsbin,kentcdodds/jsbin,roman01la/jsbin,HeroicEric/jsbin,KenPowers/jsbin,dennishu001/jsbin,peterblazejewicz/jsbin,saikota/jsbin,thsunmy/jsbin,IvanSanchez/jsbin,ctide/jsbin,martinvd/jsbin,juliankrispel/jsbin,AverageMarcus/jsbin,late-warrior/jsbin,jasonsanjose/jsbin-app,roman01la/jsbin,late-warrior/jsbin,ilyes14/jsbin,jsbin/jsbin,knpwrs/jsbin,minwe/jsbin,mdo/jsbin,y3sh/jsbin-fork,y3sh/jsbin-fork,simonThiele/jsbin,remotty/jsbin,jsbin/jsbin,filamentgroup/jsbin,digideskio/jsbin,blesh/jsbin,jasonsanjose/jsbin-app,johnmichel/jsbin,pandoraui/jsbin,kentcdodds/jsbin,martinvd/jsbin,peterblazejewicz/jsbin,fend-classroom/jsbin,francoisp/jsbin,mcanthony/jsbin,minwe/jsbin,thsunmy/jsbin,IvanSanchez/jsbin,arcseldon/jsbin,IveWong/jsbin,francoisp/jsbin,mingzeke/jsbin,Freeformers/jsbin,fgrillo21/NPA-Exam