[PATCH][Zesty SRU] UBUNTU: [Debian] Use default compression for all packages

[Seth Forshee]

On Thu, Apr 27, 2017 at 11:53:05AM -0500, Seth Forshee wrote:
> BugLink: http://bugs.launchpad.net/bugs/1686782
> 
> Currently we specify bzip2 compression for the main and extras
> packages, but bzip2 is no longer permitted in artful and causes
> a ftbfs. Switch to the default compression.

A couple extra details to answer questions which might arise.

The reason for needing this in zesty is that we're currently copying
forward zesty kernels to artful, where it is causing us problems.

I'm told the original reason for using bzip2 was build times. But since
we're only using bzip2 for the main and extras packages the difference
is unlikely to be substantial, and comparision of ppa builds with and
without this patch bear that out.

Seth