Make Random[] more random

[rocky]

Fixes #1221

Before change:

$ mathics -e 'Table[Random[], {6}]'
{{0.}, {0.}, {4.94066×10^-324}, {0.}, {0.}, {0.}}

After change:

mathics -e 'Table[Random[], {6}]'
{0.0480615, 0.0366987, 0.0705173, 0.283725, 0.84478, 0.138017}

Rule rewrites before change:

In[4]:= TraceEvaluation[Random[]]
  Evaluating: System`Random[]
    Evaluating: System`Random
    -> System`RandomReal[0, 1]
    Evaluating: System`RandomReal
    -> System`RandomReal[System`List[0, 0], 1]
    Evaluating: System`RandomReal
    Evaluating: System`List[0, 0]
    -> System`RandomReal[System`List[0, 0], System`List[1]]
    Evaluating: System`RandomReal
    Evaluating: System`List[0, 0]
    Evaluating: System`List[1]
    -> {5e-324}
Out[4]= {4.94066×10^-324}

[rocky]

kkpo4553@cde2b60 seems better. Changes incorporated and improved.

[mmatera]

LGTM