[ipkg] Port the full ipkg to Kamikaze

[ipkg] Port the full ipkg to Kamikaze
 - Does not suffer from most of the issues the busybox implementation experiences
 - busybox ipkg is still the default package manager
 - Removes /usr/bin/ipkg on install if it is a symlink
 - Relinks /usr/bin/ipkg to busybox on removal if ipkg is compiled into busybox
 - Supports gzip'd package lists, results in substantial space savings

SVN-Revision: 11980