new GP syntax

[Bill Allombert <Bill.Allombert@math.u-bordeaux1.fr>]

Dear PARI developers,

As discussed at the Ateliers PARI, 

I have finally added two new syntax to GP:

1) ranges: [a..b] is a shortcut for [a,a+1,...,b]:
? [1..10]
%2 = [1,2,3,4,5,6,7,8,9,10]

2) comprehension: [a(x)|x<-b,c(x)]  is a shortcut for apply(x->a(x),select(x->c(x),b))

? [x^2|x<-[1..10],isprime(x)]
%2 = [4,9,25,49]

? [x^2|x<-primes(10)]
%3 = [4,9,25,49,121,169,289,361,529,841]

Please experiment with them.

Cheers,
Bill.