Refactor: rename temporary directories
Refactor: rename temporary directories

The temporary directories for image creation and building the OS both
started with 'image' as their names followed by some random
characters.  During debugging this is annoying, because on first sight
it is not clear, where which files are stored.

This patch renames them to dib_build.XXXXXXXX and dib_image.XXXXXXXX.

This patch introduces no user-visible change:
the temporary directories are only used during the
run of disk-image-builder.

Change-Id: I249cdb7750fe9a746b375b462789cd9b82681a2e
Signed-off-by: Andreas Florath <b15c342f1de186996bcca5e1a23cd684d2fadb32@florath.net>

switch-ch/diskimage-builder,zioproto/diskimage-builder,switch-ch/diskimage-builder,openstack/diskimage-builder,zioproto/diskimage-builder,openstack/diskimage-builder