Log message:
Drop superfluous PKG_DESTDIR_SUPPORT, "user-destdir" is default these days.
Mark packages that don't or might probably not have staged installation.

Log message:
Import mmdb-1.21 as wip/mmdb.

MMDB is CCP4\'s macromolecular coordinate library, written by Eugene Krissinel
of the EBI. The Coordinate Library is designed to assist CCP4 developers in
working with coordinate files. The major source of coordinate information
remains the PDB files, although more information becomes available in
mmCIF format. The Library features working with both file formats plus an
internal binary format portable between different platforms. This is achieved at
uniformity of the Library\'s interface functions, so that there is no difference
in handling different formats. The Library provides various high-level tools for
working with coordinate files, which include not only reading and writing, but
also orthogonal-fractional coordinate transforms, generation of symmetry mates,
editing the molecular structure and some others. The Library is supposed as a
general low-level tool for unifying the coordinate-related operations.