Add values to enum entries

Hello,

In our C code we give values to our enum entries, I modified cwrap so that it takes those values.
This code break some tests but I think it's not a big deal, it just add values to enum where there wasn't.

eg.:

enum toto {
    enum1,
    enum2,
    enum3
};

will give 

ctypedef enum toto:
    enum1 = 0
    enum2 = 1
    enum3 = 2

Thanks for all your work,

XL.