fix: numberOfConesOfDimension

subprocedure for ConeCollections does not work for now,
added ensureComplex()
fix: missed assume for allowing empty bigintmats
chg: print routines for polyhedral fans

corresponds to 7add05a9a5fb7b1e61023a1b6873e366d004d453 in master
chg: print routines for polyhedral cones

corresponds to a2e8ff135c1975091940c626c92759347447fa73 in master
new: first try in polymake interface
Merge pull request #342 from YueRen/spielwiese

Spielwiese