This command is used to test the performance of cryptographic
algorithms.
OPTIONS
-engine id
specifying an engine (by it's unique id string) will cause
speed to attempt to obtain a functional reference to the specified
engine, thus initialising it if needed. The engine will then be
set as the default for all available algorithms.
[zero or more test algorithms]
If any options are given, speed tests those algorithms, otherwise
all of the above are tested.
