Remove delay options

These were exposed to users, but have subsequently been removed as
sockopts. They are currently only being used by ZAP, so I've moved it to
a simpl function call (actually it's only used in one case even in that,
so there may be a further simplification possible there).
Merge in master changes
fix type on HWM
Merge pull request #628 from ianbarber/master

Remove delay options