Change storage test generator

1. Now it finds disks from all local storage instead of checking PRIMARY disk only.
2. Updated find bus/pci info of storage that was not working well with some setup
3. All the interfaces, that have local disk(s) attached and local SR is created, will be selected to test.
4. Make storage test to run against given SR
Merge pull request #68 from bpwook/localstorage

Change storage test generator