Deb packaging repo changes

Hi all,

Just a heads up for all those that care about the deb packaging files - I'm
switching to using branches for each of the repo types. That means we'll


The intention is to only commit new changes to the nightly branch (from
which we can easily test changes to the packaging). From there we can
squash-merge down to the other two repos whenever a new release is made.
Not directly committing to the other two repos should make such operations
fairly easy.

As such, if anyone was preparing patches for the packaging files, send the
PRs to the nightly branch.

The actual build method is unaffected, and the final deb repo on is also unaffected - this is just an internal change to
simplify moving changes between the repo types.