Add series of changes to get source to build on launchpad

 Launchpad doesn't provide a deb-src uri in their chrooted
 environment so this commit documents the series of changes
 that were attempted to get the varnish source downloaded
 using apt so that we can ensure the correct varnish version
 is downloaded for the correct distribution.

 It also documents in a series of patches an attempt to
 bypass the need of the varnish source. Unfortunately, there
 are some header files in the varnish source that don't yet
 exist in the libvarnishapi-dev package, and since time is
 of the essence, downloading the source ultimately made the
 most sense.
Remove no longer used patches
Add explanation in rules file