Change HAVE_LZMA -> HAVE_LZMA_STATIC.

This is a mechanical change.
Use 'pod2man -u' to generate UTF-8 manual pages.
Add experimental support for gzip-compressed cpio image files.

You can now do:

  gzip -9 supermin.d/*.img

and the cpio files will be transparently uncompressed by
supermin-helper.  Note that compressing 'hostfiles' is not supported.