restrict http version for ruby 1.8.7
restrict http version for ruby 1.8.7

xuwupeng2000/webmock,hilben/webmock,hobodave/webmock,henrik/webmock,taiki45/webmock,avantcredit/webmock,VincentZhao/webmock,Omnihuron/webmock,sinisterstuf/webmock,davidbegin/webmock,spjsschl/webmock,arronmabrey/webmock,maruware/webmock,bblimke/webmock