[Fluxus] randomness commits

[Dave Griffiths]

Also some new functions for randomness in CVS. These can replace flxrnd
and use the plt random number generator

(rndf)     number between 0 and 1
(crndf)    number between -1 and 1
(grndf)    gaussian random number (average 0)

Also a load of vector random calls. It helps to think of these in terms
of the shape they would make if you plot them as particle clouds - there
are examples in the docs to do this:

(rndvec)   all elements 0->1 (solid unit cube)
(crndvec)  all elements -1->1 (solid cube centred on origin)
(srndvec)  vectors with length less than 1 (solid sphere with radius 1)
(hsrndvec) vectors of length 1 (hollow sphere with radius 1)
(grndvec)  gaussian - normal distribution around 0,0,0

cheers,

dave