Fix unit tests from hanging
Fix unit tests from hanging

Bug was introduced in 0.8.7 of httpretty
that causes testes to hang.  Requiring <=0.8.6
for now.

bleib1dj/boto,ramitsurana/boto,weebygames/boto,vijaylbais/boto,shaunbrady/boto,weka-io/boto,awatts/boto,campenberger/boto,zzzirk/boto,stevenbrichards/boto,SaranyaKarthikeyan/boto,s0enke/boto,nishigori/boto,trademob/boto,varunarya10/boto,podhmo/boto,nexusz99/boto,Pretio/boto,darjus-amzn/boto,Asana/boto,acourtney2015/boto,yangchaogit/boto,israelbenatar/boto,vishnugonela/boto,garnaat/boto,alfredodeza/boto,felix-d/boto,rosmo/boto,khagler/boto,jindongh/boto,clouddocx/boto,janslow/boto,ekalosak/boto,j-carl/boto,rayluo/boto,zachmullen/boto,ocadotechnology/boto,elainexmas/boto,nikhilraog/boto,ryansb/boto,bryx-inc/boto,dimdung/boto,jotes/boto,abridgett/boto,revmischa/boto,TiVoMaker/boto,pfhayes/boto