require MatricesForhomalg v2013.01.09

(MatricesForhomalg v2013.01.09:
 internal rings now look for RP!.{Zero,One,MinusOne} first;
 installed corresponding methods)
fixed SI_ZeroColumns and SI_ZeroRows

. no need to pass the ring as the second argument
. Frank did "Unbind(SI_vector);" in libsing e6189e3eb
got rid of obsolete methods for IsSingularPoly
renamed RingMacrosForGAPWithSingularForHomalg init_string

$init_string_SingularForHomalg -> !init_string_SingularForHomalg

(needs HomalgToCAS v2013.01.09:
 InitializeMacros now supports '!'-entries for init_strings)