Support sets, polytopes, and feasibility of linear-inequality systems.

This library contains three different methods for deciding on the
feasibility of a linear-inequality system.
These algorithms are independent from the data structures for support
sets and faces of polytopes.

1. Linear-programming solver, efficient to extract vertices :

     dictios         Dictionaries
     lp              Linear_Programming

2. Implementation of Farkas lemma with generation of k-faces :

     givens          Givens_Rotations
     farkas          Farkas_Lemma
     int_farkas      Integer_Farkas_Lemma
     facenu_ut       Face_Enumerators_Utilities
     facenum         Face_Enumerators
     fltfanum        Float_Face_Enumerators

3. Primal-dual algorithm with inconsistency proof :

     flt_lis         Float_Linear_Inequality_Solvers

4. Integer and floating-point lists, support function and faces :

     lstivc          Lists_of_Integer_Vectors
     lstivc_io       Lists_of_Integer_Vectors_io
     arrlivc         Arrays_of_Integer_Vector_Lists
     arrlivc_io      Arrays_of_Integer_Vector_Lists_io
     intsupfu        Integer_Support_Functions
     intfaces        Integer_Faces_of_Polytope
     intfaces_io     Integer_Faces_of_Polytope_io

     lstfvc          Lists_of_Float_Vectors
     lstfvc_io       Lists_of_Float_Vectors_io
     arrlfvc         Arrays_of_Float_Vector_Lists
     arrlfvc_io      Arrays_of_Float_Vector_Lists_io
     fltsupfu        Float_Support_Functions
     fltfaces        Float_Faces_of_Polytope
