This allows for more than two keyrings to be used.

Remove code to handle bug closures differently for NMUs or experimental uploads and just let version tracking sort it out instead.

[rmurray] change default compression scheme for both Sources and Packages to gzip and bzip2 rather than uncompressed and gzip (Packages) and gzip (Sources).  Use old defaults for proposed-updates.

[rmurray] BTS pseudo packages: drop install, installation, boot-floppy, slink-cd, potato-cd and nonus.debian.org.  Update base.

ensure the Source: field in changes files is a package name.  Support new dpkg optional version in the field, too.

fix, and stats fix.