[B.A.T.M.A.N.] Quagga zebra API client for BATMAN

Hello ppl,

I've added support to send BATMAN routes to zebra daemon and redistribute them to other Quagga protocols. The interface is through zebra UNIX socket. A new option -q followed by the UNIX socket path is added (see batmand --help) to enable route export. I've also implemented a metric for BATMAN routes based on TTL value which is essential when using BATMAN as IGP to BGP Confederations.

I hope that you find it useful.

The attached patches are against latest stable BATMAN release (revsion 502) and Quagga 0.98.6.

Regards, Vasilis