Fixed a problem with the set seed method.
Changed random number generator, and made som fixes of the acceptance rate which came when I added the thermalization. Passes tests.
Added commandline argument for integral solver.
Fixed problem with methods when parallelized, by adding a retrun 0 statement for the slave precesses.
Added MPI barriers in the output functions as a remedy to problems with the output, where the integral value was wrong at the large N values.