Add support of limited repetitions

[SicroAtGit]

Syntax	Meaning
x{n,m}	at least n of x and at most m of x
x{n,}	at least n of x
x{,m}	at most m of x
x{n}	exactly n of x

If n is greater than m an error is triggered.

[SicroAtGit]

I will implement this in one of the next major versions, because it is a breaking change.