Library Interface to Quantum ESPRESSO

This package allows calling programs of the Quantum Espresso package as
subroutines. At the moment this feature is restricted to do something
similar to calling an executable with the corresponding flags through
the system() command. This is useful for building hybrid parallel programs
where multiple executables, or multiple copies of the same executable
are sharing a single MPI communicator and need to exchange information
during the run.

Additional APIs will be added as the need arises.

Authors:
Axel Kohlmeyer <akohlmey@gmail.com>