When an underlying block device (or driver) only supports 4KB IO,
this can cause some issues with aspects like using an ISO9660 filesystem
which can only support a maximum of 2KB IO.
The agent will now attempt to mount the filesystem *before* deleting the
supplied file, and should that fail it will mount the configuration drive
file from the ramdisk utilizing a loopback, and then extract the contents
of the ramdisk into a newly created VFAT filesystem which supports 4KB
block IO.
Closes-Bug: #2028002
Change-Id: I336acb8e8eb5a02dde2f5e24c258e23797d200ee
b6c263a5dc