cssCode Quantum CSS codes
 objects are CSS codes, inputs are gf(2) matrices
 To create a hypermap-homology code from a hypermap H, do
 Hcode=cssCode(gf(boundaryDartModEdgeToVertex(H)),gf(boundaryFaceToDartModEdge(H))');
 
 cssCode properties:
    Hx - The first binary matrix in CSS construction
    Hx - The second binary matrix in CSS construction
 
 cssCode methods:
    cssCode - construct a CSS code given two binary matrices with HxHz'=0
    N - the length N of the code
    K - the dimension K of the code
    minDist - the minimum distance of the code
    argMinDist - the minimum distance of the code and the codewords that
    attain that minimum distance
    argMinDistWeighted - the minimum distance of the code and the codewords
    that attain that minimum distance, based on a given weighting on the distance