Implement support to verifyCPF operator into libmodsecurity

[zimmerle]

Operator verifyCPF needs to be implemented inside libmodsecurity.

The documentation of the operator can be found here:
https://github.com/SpiderLabs/ModSecurity/wiki/Reference-Manual#verifyCPF

The file already exist in the repository:
https://github.com/SpiderLabs/ModSecurity/blob/libmodsecurity/src/operators/verify_cpf.cc

[zimmerle]

Added. 25175dd.