MultiDict and HeaderDict cleanup and speedup.
MultiDict and HeaderDict cleanup and speedup.

api: MultiDict.[iter]items() now returns all items. iterallitems() is obsolete.

kevintaw/bottle,Kjuly/bottle,mrdon/bottle,samstav/bottle,ericfrederich/bottle,wangjun/bottle,wangjun/bottle,StdioA/bottle,defnull/bottle,adampresley/bottle,fkazimierczak/bottle,hkmshb/bottle,bottlepy/bottle,khirayama/bottle,khirayama/bottle,oz123/bottle,AWFU/bottle,gaotongfei/bottle,SmithSamuelM/bottle,SmithSamuelM/bottle,kevintaw/bottle,Kjuly/bottle,catroot/bottle,ifduyue/bottle,catroot/bottle,taisa007/bottle-ja,StdioA/bottle,defnull/bottle,myzhan/bottle,enzzc/bottle,CentricWebEstate/bottle,SamuelMarks/bottle,oz123/bottle,hayate/bottle,ListFranz/bottle,xsank/bottle,Inndy/bottle,AWFU/bottle,ListFranz/bottle,kevinmel2000/bottle,samstav/bottle,Inndy/bottle,myzhan/bottle,ifduyue/bottle,CentricWebEstate/bottle,mefyl/bottle,enzzc/bottle,prologic/bottle,kevinmel2000/bottle,prologic/bottle,SamuelMarks/bottle,bottlepy/bottle,mrdon/bottle,adampresley/bottle,hayate/bottle,mefyl/bottle,fkazimierczak/bottle,ericfrederich/bottle,gaotongfei/bottle,hkmshb/bottle,taisa007/bottle-ja