Test sending rng seeds over the network

This test makes a series of configs which look like rng seed updates,
sends them using the network layer, and recieves them, and checks the
integrity. It includes hex strings which are all numeric and begin
with leading zeros, to be sure that the leading zeros are not
truncated. The list of seeds is duplicated from part of test_rng.cpp.
require random 1.40.0 only, use ctime if WIN32 && boost_v < 1.43.0

Fixup seed_rng to check for windows and boost version < 1.43.0.
This allows to downgrade boost random lib requirement to 1.40.0.
move boost::random_device from file scope to local static
fixup copyright notification in seed_rng.?pp
fixup copyright notification in mt_rng.?pp