Replace Matrix#row_count with Matrix#row_size
Replace Matrix#row_count with Matrix#row_size

Rambatino/pi-ruby,zalt50/iruby,SciRuby/iruby,zalt50/iruby,zalt50/iruby,hainesr/iruby,domitry/iruby,Rambatino/pi-ruby,hainesr/iruby,SciRuby/iruby,domitry/iruby,SciRuby/iruby,zalt50/iruby,SciRuby/iruby