Add some mild thread documentation
Add some mild thread documentation

since reading the code is probably incredibly confusing now.

dianerdianer/memcached,EdwardLee03/memcached,romanticode/memcached,rmccullagh/memcached,sagark/memcached-accel,niaomingjian/memcached,surajdharmapuram/memcached,angusfenying/memcached-win64,romanticode/memcached,samanbarghi/memcached,leedc/memcached,13693100472/memcached,rhli/memcached,romanticode/memcached,samt42/memcached,memcached/memcached,angusfenying/memcached-win64,13693100472/memcached,tmharrisonwang/memcached,xiaosl/memcached,emcconville/memcached,zaycev/memcached,Dhruva6/memcached,DSrcl/memcached,Distrotech/memcached,ZhangZhenhua/memcached,cloudrain21/memcached,fengshao0907/memcached,rhli/memcached,neutronsharc/memcached,tellapart/memcached,jeremiahyan/memcached,rmccullagh/memcached,sagark/memcached-accel,neutronsharc/memcached,surajdharmapuram/memcached,gencer/memcached,leedc/memcached,ZhangZhenhua/memcached,kamyu104/memcached,tomykaira/memcached,mitliucak/memcached,jbergstroem/memcached,niaomingjian/memcached,fengshao0907/memcached,myPublicGit/memcached,amyvmiwei/memcached,leedc/memcached,xiaosl/memcached,alexandermerritt/memcached,Dhruva6/memcached,dkrotx/memcached-dd,alexandermerritt/memcached,tmharrisonwang/memcached,elfchief/memcached,msg7086/repcached,emcconville/memcached,rhli/memcached,msg7086/repcached,leedc/memcached,williamcheungthu/memcached,samt42/memcached,dkrotx/memcached-dd,tmharrisonwang/memcached,ClearwaterCore/memcached,williamcheungthu/memcached,guikcd/memcached,cloudrain21/memcached,romanticode/memcached,ZhangZhenhua/memcached,samt42/memcached,rmccullagh/memcached,tmharrisonwang/memcached,Distrotech/memcached,dkrotx/memcached-dd,ClearwaterCore/memcached,xiaosl/memcached,mitliucak/memcached,kamyu104/memcached,DigitalAce/memcached,elfchief/memcached,bpzhang/memcached,leverich/memcached-affinity,surajdharmapuram/memcached,dkrotx/memcached-dd,bpzhang/memcached,mitliucak/memcached,samanbarghi/memcached,cloudrain21/memcached,gencer/memcached,13693100472/memcached,memcached/memcached,angusfenying/memcached-win64,ClearwaterCore/memcached,fengshao0907/memcached,allen8807/memcached-1,dormando/memcached,EdwardLee03/memcached,guikcd/memcached,jeremiahyan/memcached,fengshao0907/memcached,niaomingjian/memcached,dormando/memcached,cloudrain21/memcached,Dhruva6/memcached,jeremiahyan/memcached,amyvmiwei/memcached,jbergstroem/memcached,tomykaira/memcached,williamcheungthu/memcached,samanbarghi/memcached,guikcd/memcached,Danzeer/memcached,rmccullagh/memcached,sagark/memcached-accel,amyvmiwei/memcached,memcached/memcached,rhli/memcached,neutronsharc/memcached,alexandermerritt/memcached,DSrcl/memcached,bpzhang/memcached,memcached/memcached,DigitalAce/memcached,gencer/memcached,gencer/memcached,EdwardLee03/memcached,EdwardLee03/memcached,leverich/memcached-affinity,myPublicGit/memcached,elfchief/memcached,allen8807/memcached-1,memcached/memcached,alexandermerritt/memcached,myPublicGit/memcached,gencer/memcached,elfchief/memcached,dianerdianer/memcached,Danzeer/memcached,angusfenying/memcached-win64,jeremiahyan/memcached,dianerdianer/memcached,allen8807/memcached-1,sagark/memcached-accel,zaycev/memcached,DSrcl/memcached,bpzhang/memcached,13693100472/memcached,neutronsharc/memcached,msg7086/repcached,zaycev/memcached,leverich/memcached-affinity,williamcheungthu/memcached,myPublicGit/memcached,guikcd/memcached,dormando/memcached,dormando/memcached,tellapart/memcached,samanbarghi/memcached,guikcd/memcached,emcconville/memcached,allen8807/memcached-1,Danzeer/memcached,zaycev/memcached,samt42/memcached,amyvmiwei/memcached,Distrotech/memcached,rmccullagh/memcached,emcconville/memcached,xiaosl/memcached,jbergstroem/memcached,DSrcl/memcached,tomykaira/memcached,ClearwaterCore/memcached,dormando/memcached,kamyu104/memcached,dianerdianer/memcached,mitliucak/memcached,niaomingjian/memcached,msg7086/repcached,Dhruva6/memcached,ZhangZhenhua/memcached,DigitalAce/memcached,tomykaira/memcached,tellapart/memcached,13693100472/memcached,elfchief/memcached,surajdharmapuram/memcached,sagark/memcached-accel,kamyu104/memcached,Danzeer/memcached,msg7086/repcached