Delete the examples/aurneeded.pl script.

The example is written for the old ALPM module and needs
to be rewritten but I don't really want to bother.
Rename pkgrels to pkglinks in get_pkgvars's result.
Rewrite the docs for get_pkgvars.
Update the Changes file for the new release.
Remove examples/aurneeded.pl from MANIFEST.
Add acme file to MANIFEST.SKIP.