remove redundant character '/' about epel url
remove redundant character '/' about epel url

Avoiding redundant '/' after epel at etc/yum.repos.d/base.repo
like "baseurl=http://mirror.yandex.ru/epel//6/x86_64/" in SANDBOX.

Change-Id: I5644f3ca84be4e50ef7d6888f59899336d663ff6

huntxu/fuel-main,SergK/fuel-main,eayunstack/fuel-main,eayunstack/fuel-main,huntxu/fuel-main,stackforge/fuel-main,SergK/fuel-main,eayunstack/fuel-main,stackforge/fuel-main,SergK/fuel-main,stackforge/fuel-main,huntxu/fuel-main