Revisit fio image for storage tests (#405)
Revisit fio image for storage tests (#405)

1. Based on rhel7 instead of centos.
   This certainly makes pkg installation harder because subscription.
2. Use the same yum-repo files as AMI provisioner.

So the only features required by fio tests:
A. ssh access to the running pod
B. pbench-agent and pbench-fio are installed
mrsiano/svt,mffiedler/svt,mffiedler/svt,mrsiano/svt,mrsiano/svt,vikaslaad/svt,vikaslaad/svt,vikaslaad/svt,vikaslaad/svt,vikaslaad/svt,mffiedler/svt,mrsiano/svt,mrsiano/svt