mesheR - goodbye Fortran, hello OpenMP

Despite all the stuff waiting on my desk, I decided to switch from Fortran to C++ for my package mesheR. Thanks to RcppArmadillo this was pretty much a piece of cake and the only delay was owed to my tiredness. The cool thing was that (other than in Fortran) OpenMP parallelization worked out of the box. Both elastic icp functions AmbergRegister and gaussMatch are much faster now (especially on my shiny new hexacore workstation ;)).