Bug#839046: debootstrap: enable --merged-usr by default
As mentioned earlier, I would like to see --merged-usr enabled by
default for Debian Stretch. The last discussion on -devel@ was quite
positive; I had some additional positive feedback on IRC.
I'm not aware of any regressions so far, except for having forgotten to
add "jessie-kfreebsd" to the blacklist (a list of older releases that
don't support merged-/usr) and debootstrap 1.0.83 failing to bootstrap
squeeze. Both are fixed in my changes targeted at 1.0.84.
So I would like to switch the default in debootstrap sooner rather than
later to give time to find some more bugs. With this change, the
currently known bugs should also be raised to "serious", but I don't
think any of them should be a blocker.