License change: MMTK is now distributed under the CeCILL-C license,
which is an adaptation of the LGPL to French law. The previously used
CeCILL license, similar to the GPL, was considered too restrictive.

New features:

- PDBConfiguration: new method createUnitCellUniverse() creates an empty
  universe that has the shape of the unit cell from the PDB file.

- PDBConfiguration: new method asuToUnitCell() applies crystallographic
  symmetry operations to the molecules in the asymmetric unit.

- PDBConfiguration: accept file objects as well as file names.


Improvements:

- The residue name list in Scientific.IO.PDB is now synchronized with the
  one in MMTK, meaning that all residues defined as such in MMTK will
  also be recognized when reading PDB files.


Bug fixes:

- NormalModes objects handle temperature=None correctly when calculating
  fluctuations.

- PDBMoleculeFactory now works with PDB configurations that have no
  symmetry information.

- Opening a trajectory for reading could crash depending on the force field
  used in the system.

- Proteins with disulphide bonds between chains had an inconsistent
  internal representation that would cause a crash when writing
  to a PDB file.

- More alternative PDB atom names for ribose.

- Fixed installation with NumPy under Windows.