Allow E-field parallel to semi-infinite direction when using just one electrode
When using just one electrode, it is apparently possible (communication from P. Ordejón) to have an electric field in the "transport" direction. Then, this check in dhscf:
call die('User defined E-field must be perpendicular to semi-infinite directions.’)
might be turned into a warning, or otherwise removed.
Some extra code is then needed to check that the field is indeed compatible, and unlock this feature.