WIP: implement RandomDevice RNG

This introduces a new `AbstractRNG` in Base, whose logic was already used to seed RNGs from OS entropy pool. See #9274 where the discussion on this statred.
   
Is this endian-safe? I would say no, in which case the simplest would be to always read 128 bits. WDYT?
Also, I don't have a windows installation to test this `RandomDevice` version.