backend extensible updates. closes #227
backend extensible updates. closes #227

yesodweb/persistent,mkscrg/persistent,meteficha/persistent,mkscrg/persistent,meteficha/persistent,andrewthad/persistent,andrewthad/persistent,superduper/persistent,mitchellwrosen/persistent,mitchellwrosen/persistent,meteficha/persistent,rdnetto/persistent,superduper/persistent,gbwey/persistent,gbwey/persistent,psibi/persistent,jasonzoladz/persistent,nakaji-dayo/persistent,jcristovao/persistent,nakaji-dayo/persistent,pseudonom/persistent,mitchellwrosen/persistent,pseudonom/persistent,jcristovao/persistent,jasonzoladz/persistent,jasonzoladz/persistent,jcristovao/persistent,greydot/persistent,erikd/persistent,andrewthad/persistent,nakaji-dayo/persistent,paul-rouse/persistent,naushadh/persistent,bitemyapp/persistent,creichert/persistent,greydot/persistent,greydot/persistent,superduper/persistent,junjihashimoto/persistent,mkscrg/persistent,plow-technologies/persistent,junjihashimoto/persistent,gbwey/persistent,rdnetto/persistent