1. Do not pass request_reply_timeout and request_reply_retry_delay
to OnionMessageManager.
Arguments passed to a function are useful only if their value might
change during the execution of a program. If that is not the case,
it is preferable to define them as constants. That makes the code
easier to read, because the reader can focus on arguments that are
actually relevant.
2 . Multiply all time constants by the same factor, instead
of doing so incompletely and on a per parameter basis. (note
that before this commit, the speedup factor was not consistent)
3. Do not use util.now(), because it is rounded as integer.
With these changes, the tests can effectively run with a 100x speedup
