Minor: removed some commented-out code and some more stuff for doing timing; better to do that with a profiler.
Merge branch 'master' of https://github.com/NAVADMC/SpreadModel
Basic plumbing to allow modules to report errors in parameter validation. Next step is to change assertions in the individual parameter reading routines to report errors in GError format. Will still need more work to consistently use GError error reporting throughout the rest of the code. #185