Only emigrate of population at capacity
Immigration/emigration influenced by sex ratio
restrict im(e)migration prob to be 0-1
Tighter migration rules: keep pop size within 10% of capacity, bound rates at 0-1
Tighter migration rules: keep pop size within 10% of capacity, bound rates at 0-1
Merge branch 'master' of psy-b18-2.psy.ed.ac.uk:/home/mjadams/git/slowlane