How to convert unix to NaiveDateTime?

[benwilson512]

@wojtekmach

note, I removed the trailing 388 , the milliseconds, as the function only accepts whole seconds,

This can be changed with an argument:

iex(1)> 1466329342388 |> DateTime.from_unix!(:millisecond) |> DateTime.to_naive()
~N[2016-06-19 09:42:22.388]