Various dist.sh changes.
Various dist.sh changes.

* dist.sh
  Add -apr, -apu, -neon parameters to allow the paths be specified to them.
  Add -beta and -alpha parameters to allow the type of release to be specified.
  Allow path to svn command to be overridden by SVN environment variable,
    this will be useful for boot strapping a tarball when the system doesn't
    already have an installed svn command on the path.
  No longer generate the tar twice, compress with bzip2 first and keep the
    tar file around so we only have to invoke pax once.
  Don't invoke ls twice.
  Output md5sums at the end of the process.
  No longer assume that the branch we're generating out of has a svn_version.h
    marked up like a -dev tree, we might be generating against a tag, e.g.
    when we do security releases.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion