implements the order polytope and chain polytope of a poset

Imported from <a href="http://trac.sagemath.org/sage_trac/ticket/13507">trac #13507</a>.



Reported by: chapoton

Component: combinatorics

CC: sage-combinat

Report Upstream: N/A

Authors: Frédéric Chapoton

Dependencies: 

Work issues: 

Reviewers: Alejandro Morales

Merged in: sage-5.9.beta1

Attachments: <ol><li><a href="http://trac.sagemath.org/sage_trac/attachment/ticket/13507/trac_13507_order_polytope-fc.patch">trac_13507_order_polytope-fc.patch: </a> by chapoton at 20130318T20:35:23</li></ol>