Separating two different behaviours of the random command

Currently, the `random` command presents two quite different behaviours:
+ if the two arguments are different, returns a random integer value between the lowest argument included and the highest argument excluded.
+ if both arguments are the same, returns a random floating point value between them (included) and their successor (excluded).

I find this duality rather confusing, on top of the fact that, in my opinion, "a random value between 1 and 2" should mean "either 1 or 2", not "always 1". And "A random value between 4 and 4" should be "always 4", not "4.145812471782441".

So I'd like to change that. This `random` command returns an integer between x and y (or 0 and x if only 1 argument is provided), both included. Additionally, the `random_figures` (the name could use a change I guess) command (no argument) returns a random floating point value between 0 and 1.