Organization of the C library

• Files `config.h' and `pkint.h' respectively define some configuration stuff and the operations on generic integers.
• `polka.c' and `polka.h' define global variables that set the operation mode and the maximum size of matrices, and the initialization finalization functions.
• `internal.c' and `internal.h' define the internal global variables.
• `bit.c' and `bit.h' define types bitstring_t and bitindex_t that allow to acces and perform operations on bitstrings.
• `satmat.c' and `satmat.h' define the type satmat_t of saturation matrices and the needed operations.
• `vector.c' and `vector.h' define operations on vector, considered as C arrays;
• `matrix.c' and `matrix.h' define the type matrix_t and needed operations on it, including rows sorting, matrices merging, transformation by assignation or substitution of a variable by an affine transformation;
• `cherni.c' and `cherni.h' contain the conversion and minimization algorithms;
• last, `poly.c' and `poly.h' define the poly_t and operations on polyhedra.

In principle, a user needs only to know the `polka', `vector', `matrix' and `poly' interfaces, and some of `pkint'.