tests: add dbus example to traverse the devices and call test the Factory()

[trgill]

Added block device list as "--blockdevs" parameter. It accepts block devices in the format "/dev/xxx,/dev/xxx".

Call the Factory() to test DEVICE_TYPE_LVM, DEVICE_TYPE_BTRFS, DEVICE_TYPE_MD and DEVICE_TYPE_STRATIS.

[StorageGhoul]

Can one of the admins verify this patch?

[trgill]

@vojtechtrefny @dwlehman would it make sense to merge this as an example?

I think we might want to add something similar to automated tests?

These calls are what the CSI driver uses - just FYI.

[vojtechtrefny]

Jenkins, ok to test.

[vojtechtrefny]

@vojtechtrefny @dwlehman would it make sense to merge this as an example?

Definitely, more examples could never hurt.