This makes it possible to build an image against a first distribution
(--distribution-chroot) and have the resulting image point to another
distribution (--distribution-binary). We can use this to build against a
snapshot and have the result use the original distribution that was
snapshotted.
Closes: #888507
The apt-secure option does not work anymore when building a sid image,
as with apt 1.6 the existing options are no longer enough to get apt
to accept an unsigned repository, which is necessary when using a
local cached repository (offline build).
Pass Acquire::AllowInsecureRepositories "true"; together with the
other options when --apt-secure false is used to fix the issue.
Previously, we needed to keep the lb_* prefix as the scripts
could also be executed standalone. Since the lb wrapper is
mandatory since squeeze, we can drop this now.