add test for issue_260
add test for issue_260

Only for posterity... See notes in the test file for how to use it. Test is
normally skipped. Will cause an assert under old versions of memcached.

alexandermerritt/memcached,memcached/memcached,cloudrain21/memcached,EdwardLee03/memcached,amyvmiwei/memcached,msg7086/repcached,Dhruva6/memcached,amyvmiwei/memcached,bpzhang/memcached,jeremiahyan/memcached,dormando/memcached,gencer/memcached,msg7086/repcached,guikcd/memcached,alexandermerritt/memcached,romanticode/memcached,DSrcl/memcached,cloudrain21/memcached,surajdharmapuram/memcached,williamcheungthu/memcached,romanticode/memcached,mitliucak/memcached,amyvmiwei/memcached,allen8807/memcached-1,allen8807/memcached-1,surajdharmapuram/memcached,gencer/memcached,13693100472/memcached,Dhruva6/memcached,xiaosl/memcached,niaomingjian/memcached,dormando/memcached,elfchief/memcached,dormando/memcached,Danzeer/memcached,ClearwaterCore/memcached,angusfenying/memcached-win64,rhli/memcached,rhli/memcached,surajdharmapuram/memcached,elfchief/memcached,Danzeer/memcached,kamyu104/memcached,amyvmiwei/memcached,samanbarghi/memcached,jeremiahyan/memcached,tmharrisonwang/memcached,tmharrisonwang/memcached,samt42/memcached,myPublicGit/memcached,williamcheungthu/memcached,xiaosl/memcached,guikcd/memcached,rmccullagh/memcached,niaomingjian/memcached,bpzhang/memcached,ZhangZhenhua/memcached,Dhruva6/memcached,neutronsharc/memcached,rmccullagh/memcached,kamyu104/memcached,dianerdianer/memcached,neutronsharc/memcached,emcconville/memcached,mitliucak/memcached,fengshao0907/memcached,mitliucak/memcached,kamyu104/memcached,ZhangZhenhua/memcached,xiaosl/memcached,dormando/memcached,allen8807/memcached-1,jeremiahyan/memcached,msg7086/repcached,gencer/memcached,niaomingjian/memcached,myPublicGit/memcached,alexandermerritt/memcached,leedc/memcached,jeremiahyan/memcached,DSrcl/memcached,ClearwaterCore/memcached,elfchief/memcached,romanticode/memcached,guikcd/memcached,ClearwaterCore/memcached,gencer/memcached,Danzeer/memcached,leedc/memcached,gencer/memcached,rmccullagh/memcached,leedc/memcached,dormando/memcached,cloudrain21/memcached,romanticode/memcached,elfchief/memcached,tmharrisonwang/memcached,bpzhang/memcached,mitliucak/memcached,myPublicGit/memcached,samanbarghi/memcached,rmccullagh/memcached,fengshao0907/memcached,fengshao0907/memcached,DSrcl/memcached,neutronsharc/memcached,memcached/memcached,angusfenying/memcached-win64,DSrcl/memcached,dianerdianer/memcached,ClearwaterCore/memcached,samt42/memcached,dianerdianer/memcached,williamcheungthu/memcached,elfchief/memcached,emcconville/memcached,rmccullagh/memcached,dianerdianer/memcached,myPublicGit/memcached,msg7086/repcached,allen8807/memcached-1,rhli/memcached,xiaosl/memcached,EdwardLee03/memcached,leedc/memcached,fengshao0907/memcached,13693100472/memcached,samt42/memcached,13693100472/memcached,msg7086/repcached,ZhangZhenhua/memcached,rhli/memcached,13693100472/memcached,memcached/memcached,Dhruva6/memcached,emcconville/memcached,Danzeer/memcached,memcached/memcached,angusfenying/memcached-win64,guikcd/memcached,angusfenying/memcached-win64,neutronsharc/memcached,niaomingjian/memcached,EdwardLee03/memcached,ZhangZhenhua/memcached,samanbarghi/memcached,tmharrisonwang/memcached,alexandermerritt/memcached,EdwardLee03/memcached,guikcd/memcached,emcconville/memcached,samanbarghi/memcached,kamyu104/memcached,memcached/memcached,samt42/memcached,williamcheungthu/memcached,cloudrain21/memcached,surajdharmapuram/memcached,bpzhang/memcached,13693100472/memcached