MDT 5.1   09-29-2011:
 - All atom features, with the exception of atom type, are now considered
   undefined if the atom coordinates are equal to the Modeller undefined
   value (-999.0).
 - Support for bond separation, with a new AtomBondSeparation feature and
   a bond_span_range argument to Table.add_alignment().
 - Support Python 3 (requires Modeller 9.10 or later).
 - "scons test" now reports the Python coverage (and also C coverage,
   if using gcc and adding "coverage=true" to the scons command line).
 - mdt.Table() now takes an optional 'shape' argument, which acts identically
   to that accepted by mdt.Table.reshape().

MDT 5.0   03-31-2011:
 - First open source (GPLv2) release.
 - Duplicated Modeller Fortran code removed; MDT now uses Modeller itself for
   handling of protein structures and alignments.
 - Added scans over atom pairs, atom tuples, atom tuple pairs, and chemical
   bonds.
 - Complete documentation, examples, and unit tests added.
 - TOP scripting interface replaced with Python.
 - Support storing MDT tables in binary form, using the HDF5 format and
   library.

MDT 4.0  April 2002:
 - Reorganize directory structure.

MDT 3.1  March 2002:
 - Allow for a structure to be assessed against an existing MDT table.
