add ngx_pagespeed module
custom ignore files directives for dpkg-source

required because dpkg-source ignores *.a files when building a tarball.
ngx_pagespeed PSOL comes compiled so requires these files to be included
in the tarball.

The directive now uses everything the default -I directive includes except
for *.a, but there aren't any in my source tree except those for ngx_pagespeed
so the non-required file paths are specifically excluded instead.
include ngx_pagespeed binaries in the source package

x64 only right now.
ngx_pagespeed embeds some binaries

ignore this problem. unless we start building PSOL manually and can
switch to using Debian's libraries instead.