[with patch] new MQ submodule for sage.crypto

[malb]

The attached patch implements a MPolynomialSystem, a MPolynomialSystemGenerator class, and as a generator for small scale AES variants.

MPolynomialSystem is supposed to model multivariate polynomial systems as they appear in e.g. algebraic cryptanalysis. The implemented design is as follows: There is a class MPolynomialSystem which models the actual polynomial system. This class contains a list of MPolynomialRoundSystems to model the rounds of a cipher to add some structure. MPolynomialSystem is furthermore specialised to MPolynomialSystem_gf2[e] classes which have additional features. E.g. systems over GF(2^e) can be projected down to GF(2) and systems over GF(2) may eventually contain rountines for ANF-CNF conversion.

Also there is a class called MPolynomialSystemGenerator which is meant as a base class for specific generators for polynomial systems like AES or the Courtois Toy Cipher (CTC).

The patch also contains a generator for polynomial systems for small scale AES variants (SR) over GF(2) and GF(2^e) as introduced in  http://www.isg.rhul.ac.uk/~sean/smallAES-fse05.pdf .

[malb]

Great, first bugfix already. See second attachment.