New configuration options for hnet

hnet now provides configuration options (can be set using make menuconfig)

It works. But there is a little thing to fix. When changing configuration, and making again, configuration files are not modified. So if we build once for the netgear, and then for the buffalo, with the network custom config file included, the buffalo will be given the netgear's file. There probably is a way to change that with Makefile, but I didn't find out yet.