how to remove erlang:now() calls?

[dch]

There are a number of now() calls, do you want a PR simply to replace them, or with a conditional compilation flag to maintain backwards compatibility?

[benoitc]

@dch they can be replaced. If there is a way to make it compatible with pre-18 versions of Erlang then let's use it. Or next version can just handle Erlang 18 which would ease the code imo.