Some proposed changes to grab-0.2.29

Hi Greg:

This are some changes that I have to make regularly to grab.

1. Change ftp from Passive to Active.
   I do not know why I can not use ftp passive here.
   Maybe this could be an option in the configuration file ??

2. Increase limit of RPM's found from 1000 to 10000.
   Sometimes I will get over 1000 RPM in the UPGRADE list.
   For example going from mdk-8.1 to mdk-8.2 beta 2.

3. Include option -nd to wget to prevent creation of a directory structure.
   Example: system ("$bin_wget -c -r -nd -P $rpm_repository $location");