A molecular dynamics package based around self-consistent-charge density
functional tight binding theory.

Features:
* Forces computed at the SCC-DFTB level.
* Provides forces and the potential component of the total energy.
* Integrates the electronic degrees of freedom (XL) (provides charges).
* Solves the electronic structure of the system.
* Several solvers such as SP2, Truncated SP2, Chebyshev polynomial
  expansion, etc.