default random object?

[Andrei Alexandrescu]

Leonardo suggested that some functions in std.random should not require 
their user to be bothered with creating a random object, i.e.:

auto r = Random(unpredictableSeed);
auto n = uniform(r, 0, 100);

Instead the library should simply support:

auto n = uniform(0, 100);

and do this by presumably using a global RNG under the hood. So I wanted 
to ask all y'all:

1. Are you cool with making the rng the last parameter and give it a 
default value?

2. The global random generator will be allocated per thread. Are you 
cool with this too?

3. How should the global rng be initialized? To always generate the same 
sequence, or not?

4. While we're at it, should uniform(a, b) generate by default something 
in [a, b] or [a, b)? Someone once explained to me that generating [a, b] 
for floating point numbers is the source of all evils and that Hitler, 
Stalin and Kim Il Sung (should he still be alive) must be using that 
kind of generator. Conversely, generating [a, b) is guaranteed to bring 
in the long term everlasting peace to Earth. My problem however is that 
in the integer realm I always want to generate [a, b]. Furthermore, I 
wouldn't be happy if the shape of the interval was different for 
integers and floating point numbers. How to break this conundrum? Don't 
forget that we're only worrying about defaults, explicit generation is 
always possible with self-explanatory code:

auto rng = Random(unpredictableSeed);
auto a = 0.0, b = 1.0;
auto x1 = uniform!("[]")(rng, a, b);
auto x2 = uniform!("[)")(rng, a, b);
auto x3 = uniform!("(]")(rng, a, b);
auto x4 = uniform!("()")(rng, a, b);


Thanks,

Andrei