Fix RelatedSetField objects for 1.8
Fix RelatedSetField objects for 1.8

asendecka/djangae,kirberich/djangae,potatolondon/djangae,SiPiggles/djangae,chargrizzle/djangae,kirberich/djangae,jscissr/djangae,kirberich/djangae,leekchan/djangae,armirusco/djangae,SiPiggles/djangae,martinogden/djangae,chargrizzle/djangae,leekchan/djangae,wangjun/djangae,asendecka/djangae,martinogden/djangae,leekchan/djangae,jscissr/djangae,asendecka/djangae,trik/djangae,grzes/djangae,grzes/djangae,wangjun/djangae,potatolondon/djangae,wangjun/djangae,armirusco/djangae,trik/djangae,chargrizzle/djangae,grzes/djangae,trik/djangae,armirusco/djangae,martinogden/djangae,jscissr/djangae,SiPiggles/djangae