Preserve setgid bit on local directores (fixes #2012)
Preserve setgid bit on local directores (fixes #2012)

When setting the permissions on directories with ignore permissions off,
preserve the setgid bit to it's original value instead of setting it
off.

manveru/syncthing,uok/syncthing,kozec/syncthing,gillisig/syncthing,xduugu/syncthing,wweich/syncthing,modulexcite/syncthing,wsgcsysadmin/syncthing,flyzjhz/syncthing,kc1212/syncthing,le9i0nx/syncthing,alex2108/syncthing,jemmy655/syncthing,wweich/syncthing,beni55/syncthing,MinFu/syncthing,ProactiveServices/syncthing,AudriusButkevicius/syncthing,plouj/syncthing,ProactiveServices/syncthing,xduugu/syncthing,printedheart/syncthing,Zillode/syncthing,trojanspike/syncthing,wweich/syncthing,TheBigBear/syncthing,syncthing/syncthing,gillisig/syncthing,kozec/syncthing,kralo/syncthing,kralo/syncthing,plouj/syncthing,krig/syncthing,toddleish/syncthing,letiemble/syncthing,abhishekgahlot/syncthing,AudriusButkevicius/syncthing,josephyzhou/syncthing,kc1212/syncthing,buinsky/syncthing,kamadak/syncthing,mcanthony/syncthing,butlife/syncthing,trojanspike/syncthing,lkwg82/syncthing,printedheart/syncthing,printedheart/syncthing,cherylquirion/syncthing,mateon1/syncthing,michalliu/whale,kamadak/syncthing,brgmnn/syncthing,printedheart/syncthing,cherylquirion/syncthing,josephyzhou/syncthing,roth1002/syncthing,kattunga/syncthing,TheBigBear/syncthing,nrm21/syncthing,ZdenekBrichacek/syncthing,kozec/syncthing,syncthing/syncthing,jbfavre/syncthing,butlife/syncthing,toddleish/syncthing,jemmy655/syncthing,buinsky/syncthing,kamadak/syncthing,Kudalufi/syncthing,kc1212/syncthing,nrm21/syncthing,imsodin/syncthing,bigscoop/syncthing,mcanthony/syncthing,Zillode/syncthing,syncthing/syncthing,rumpelsepp/syncthing,MinFu/syncthing,atyenoria/syncthing,flyzjhz/syncthing,kc1212/syncthing,jbfavre/syncthing,atyenoria/syncthing,jryans/syncthing,wweich/syncthing,lkwg82/syncthing,makeTaller/syncthing,letiemble/syncthing,ZdenekBrichacek/syncthing,gillisig/syncthing,TheBigBear/syncthing,canton7/syncthing,le9i0nx/syncthing,canton7/syncthing,indradhanush/syncthing,itscaro/syncthing,indradhanush/syncthing,Kudalufi/syncthing,indradhanush/syncthing,wsgcsysadmin/syncthing,michalliu/whale,AudriusButkevicius/syncthing,krig/syncthing,jgke/syncthing,butlife/syncthing,danieldc/syncthing,nrm21/syncthing,Zillode/syncthing,atyenoria/syncthing,canton7/syncthing,flyzjhz/syncthing,brgmnn/syncthing,kralo/syncthing,tenebreux/syncthing,Kudalufi/syncthing,imsodin/syncthing,burkemw3/syncthing,nrm21/syncthing,imsodin/syncthing,uok/syncthing,manveru/syncthing,alex2108/syncthing,cherylquirion/syncthing,krig/syncthing,tenebreux/syncthing,jgke/syncthing,letiemble/syncthing,indradhanush/syncthing,norgeous/syncthing,itscaro/syncthing,imsodin/syncthing,jryans/syncthing,lkwg82/syncthing,jbfavre/syncthing,jryans/syncthing,makeTaller/syncthing,danieldc/syncthing,bigscoop/syncthing,pembo210/syncthing,itscaro/syncthing,plouj/syncthing,michalliu/whale,jryans/syncthing,uok/syncthing,makeTaller/syncthing,trojanspike/syncthing,buinsky/syncthing,syncthing/syncthing,trojanspike/syncthing,manveru/syncthing,josephyzhou/syncthing,letiemble/syncthing,pembo210/syncthing,kattunga/syncthing,beni55/syncthing,imsodin/syncthing,pembo210/syncthing,alex2108/syncthing,ProactiveServices/syncthing,cherylquirion/syncthing,itscaro/syncthing,mateon1/syncthing,canton7/syncthing,rumpelsepp/syncthing,alex2108/syncthing,tenebreux/syncthing,josephyzhou/syncthing,krig/syncthing,danieldc/syncthing,Zillode/syncthing,modulexcite/syncthing,syncthing/syncthing,jbfavre/syncthing,arkhi/syncthing,Kudalufi/syncthing,kluppy/syncthing,xduugu/syncthing,modulexcite/syncthing,makeTaller/syncthing,AudriusButkevicius/syncthing,norgeous/syncthing,ZdenekBrichacek/syncthing,pembo210/syncthing,lkwg82/syncthing,brgmnn/syncthing,beni55/syncthing,abhishekgahlot/syncthing,manveru/syncthing,kluppy/syncthing,abhishekgahlot/syncthing,atyenoria/syncthing,modulexcite/syncthing,toddleish/syncthing,guerrerocarlos/syncthing,MinFu/syncthing,arkhi/syncthing,kozec/syncthing,arkhi/syncthing,MinFu/syncthing,burkemw3/syncthing,jgke/syncthing,mcanthony/syncthing,burkemw3/syncthing,danieldc/syncthing,norgeous/syncthing,kluppy/syncthing,syncthing/syncthing,gillisig/syncthing,guerrerocarlos/syncthing,wsgcsysadmin/syncthing,le9i0nx/syncthing,norgeous/syncthing,kattunga/syncthing,bigscoop/syncthing,toddleish/syncthing,uok/syncthing,jemmy655/syncthing,roth1002/syncthing,ZdenekBrichacek/syncthing,xduugu/syncthing,flyzjhz/syncthing,rumpelsepp/syncthing,brgmnn/syncthing,roth1002/syncthing,buinsky/syncthing,roth1002/syncthing,tenebreux/syncthing,guerrerocarlos/syncthing,arkhi/syncthing,kamadak/syncthing,le9i0nx/syncthing,wsgcsysadmin/syncthing,mcanthony/syncthing,bigscoop/syncthing,rumpelsepp/syncthing,michalliu/whale,burkemw3/syncthing,mateon1/syncthing,plouj/syncthing,kluppy/syncthing,kralo/syncthing,beni55/syncthing,mateon1/syncthing,abhishekgahlot/syncthing,guerrerocarlos/syncthing,ProactiveServices/syncthing,jgke/syncthing,TheBigBear/syncthing,kattunga/syncthing,jemmy655/syncthing,butlife/syncthing