use Vinay's Singular package in the new subdirectory Singular
Added missing error message to Horrocks
SetNonZeroColumns for CleanRowUsingMonics
Removed AssignGeneratorVariables from examples
Declared and installed QuillenSuslin

for a row and a matrix

(Needs NoetherNormalization in MatricesForHomalg v2013.07.21)
+ Added example file QuillenSuslin.g