Fixes #1686: posixize paths in context['filenames'] to fix windows issues
Fixes #1686: posixize paths in context['filenames'] to fix windows issues

jimperio/pelican,crmackay/pelican,lazycoder-ru/pelican,talha131/pelican,Scheirle/pelican,karlcow/pelican,GiovanniMoretti/pelican,ingwinlu/pelican,TC01/pelican,UdeskDeveloper/pelican,alexras/pelican,koobs/pelican,douglaskastle/pelican,deved69/pelican-1,iurisilvio/pelican,UdeskDeveloper/pelican,garbas/pelican,karlcow/pelican,alexras/pelican,koobs/pelican,karlcow/pelican,GiovanniMoretti/pelican,joetboole/pelican,deanishe/pelican,eevee/pelican,talha131/pelican,jvehent/pelican,catdog2/pelican,kennethlyn/pelican,rbarraud/pelican,iKevinY/pelican,goerz/pelican,koobs/pelican,ehashman/pelican,getpelican/pelican,jvehent/pelican,treyhunner/pelican,iKevinY/pelican,simonjj/pelican,Rogdham/pelican,zackw/pelican,avaris/pelican,gymglish/pelican,crmackay/pelican,simonjj/pelican,TC01/pelican,Scheirle/pelican,iurisilvio/pelican,garbas/pelican,joetboole/pelican,goerz/pelican,deved69/pelican-1,UdeskDeveloper/pelican,JeremyMorgan/pelican,51itclub/pelican,jvehent/pelican,alexras/pelican,jimperio/pelican,ls2uper/pelican,Summonee/pelican,eevee/pelican,deanishe/pelican,abrahamvarricatt/pelican,ls2uper/pelican,JeremyMorgan/pelican,HyperGroups/pelican,florianjacob/pelican,douglaskastle/pelican,JeremyMorgan/pelican,GiovanniMoretti/pelican,levanhien8/pelican,51itclub/pelican,abrahamvarricatt/pelican,ls2uper/pelican,ehashman/pelican,HyperGroups/pelican,florianjacob/pelican,catdog2/pelican,51itclub/pelican,Rogdham/pelican,lazycoder-ru/pelican,levanhien8/pelican,HyperGroups/pelican,zackw/pelican,treyhunner/pelican,farseerfc/pelican,deanishe/pelican,crmackay/pelican,ingwinlu/pelican,zackw/pelican,kennethlyn/pelican,getpelican/pelican,florianjacob/pelican,Summonee/pelican,number5/pelican,lucasplus/pelican,joetboole/pelican,garbas/pelican,farseerfc/pelican,treyhunner/pelican,kennethlyn/pelican,TC01/pelican,iurisilvio/pelican,Rogdham/pelican,rbarraud/pelican,deved69/pelican-1,Summonee/pelican,number5/pelican,gymglish/pelican,simonjj/pelican,levanhien8/pelican,douglaskastle/pelican,lazycoder-ru/pelican,ehashman/pelican,avaris/pelican,Polyconseil/pelican,abrahamvarricatt/pelican,rbarraud/pelican,eevee/pelican,number5/pelican,gymglish/pelican,Polyconseil/pelican,catdog2/pelican,lucasplus/pelican,lucasplus/pelican,Scheirle/pelican,jimperio/pelican,goerz/pelican