libvirt: make guestfs methods always return list of tuples

guestfs.GuestFS supports parameter python_return_dict with default
False in 1.22 (backported in 1.20). This indicates that your program
wants to receive Python dicts for methods in the API that return list
of tuples. See http://libguestfs.org/guestfs-release-notes.1.html
In a future version of libguestfs, its default value will be True,
then that will break the code, to avoid this, we'd better force
python_return_dict as False. See http://libguestfs.org/guestfs-python.3.html

This commit makes method inspect_get_mountpoints always return list
of tuples.

Change-Id: I8211cb31a7a890f86cdd818767b3d5e8cfd5bbed
Resize block device after swap to larger volume

After swap to larger volume, instance's block device should be
resized. Otherwise, the guest can't utilize the extra space.

This patch make the libvirt driver resize block device after mirror
the volume. And add new parameter 'resize_to' to virt driver, that
is used to indicate the new size.

Change-Id: Ib4d65e8812c7d3c28100155124218c75a94e16e7
Closes-Bug: #1341459
Merge "Resize block device after swap to larger volume"
Merge "libvirt: make guestfs methods always return list of tuples"