Added an Overlap operator forward application function in the library
Currently only uses KL11 - single iteration
Two mainprogs call this overlap application:

    * normality: Computes the commutator [DD^+,D^+D] on an arbitrary
      number of gaussian vectors

    * ginsparg-wilson-relation: Computes g5D + Dg5 - Dg5D (i.e. the
      violation of the Ginsparg-Wilson relation) on an arbitrary
      number of gaussian vectors