added another multi-pk test
added another multi-pk test

wujuguang/sqlalchemy,inspirehep/sqlalchemy,Cito/sqlalchemy,sandan/sqlalchemy,alex/sqlalchemy,hsum/sqlalchemy,elelianghh/sqlalchemy,ThiefMaster/sqlalchemy,EvaSDK/sqlalchemy,monetate/sqlalchemy,276361270/sqlalchemy,dstufft/sqlalchemy,Cito/sqlalchemy,pdufour/sqlalchemy,j5int/sqlalchemy,alex/sqlalchemy,j5int/sqlalchemy,robin900/sqlalchemy,itkovian/sqlalchemy,wfxiang08/sqlalchemy,halfcrazy/sqlalchemy,WinterNis/sqlalchemy,davidfraser/sqlalchemy,davidfraser/sqlalchemy,olemis/sqlalchemy,zzzeek/sqlalchemy,epa/sqlalchemy,itkovian/sqlalchemy,wujuguang/sqlalchemy,bootandy/sqlalchemy,bootandy/sqlalchemy,276361270/sqlalchemy,sandan/sqlalchemy,brianv0/sqlalchemy,halfcrazy/sqlalchemy,WinterNis/sqlalchemy,hsum/sqlalchemy,sqlalchemy/sqlalchemy,dstufft/sqlalchemy,epa/sqlalchemy,davidjb/sqlalchemy,Cito/sqlalchemy,alex/sqlalchemy,pdufour/sqlalchemy,bdupharm/sqlalchemy,EvaSDK/sqlalchemy,monetate/sqlalchemy,brianv0/sqlalchemy,graingert/sqlalchemy,wfxiang08/sqlalchemy,olemis/sqlalchemy,ThiefMaster/sqlalchemy,bdupharm/sqlalchemy,elelianghh/sqlalchemy,Akrog/sqlalchemy,graingert/sqlalchemy,davidjb/sqlalchemy,inspirehep/sqlalchemy,robin900/sqlalchemy,Akrog/sqlalchemy