alot of bug fixes. Still debugging. Saddle energy is NaN all of a
sudden.
redid the legal to spawn checks, fixed numerous bugs. Sequential tests
failed. Implemented tests for boundary  sites and concentration wall
update. They pass. get weird assertion in affectedsites check sometimes.
The X value is not set correctly. Does this happen when a particle is
spawned at the boundary?
fixed the bug in affectedparticles. It was due to the fact that with
free particles allowed to spawn at boundaries, all directions are not a
priory allowed for diffusion.
inspected tests and found minor sources of error. Implemented security by ensuring changes in system parameters do not get transferred from test to test.