Fails to compile due to erlang:now/0 change

[mfeckie]

mix test fails due to

src/ibrowse_lib.erl:371: erlang:now/0: Deprecated BIF. See the "Time and Time Correction in Erlang" chapter of the ERTS User's Guide for more information.
ERROR: compile failed while processing /Users/XXX/Elixir/hypermock/deps/ibrowse: rebar_abort
** (Mix) Could not compile dependency :ibrowse, "/Users/XXX/.mix/rebar" command failed. You can recompile this dependency with "mix deps.compile ibrowse", update it with "mix deps.update ibrowse" or clean it with "mix deps.clean ibrowse"