optimized performance of network communication

Ignore-this: 6cc771c96c0030c06ce1b2a1f29a7d3e

I reduced the header size for the udp packets and increased the udp packet size to 1024.
However now I limited the max size of an individual message to 66.5MB

I might partition to format into two types, the small packet a jumbo one if we
need larger that 66MB messages...

darcs-hash:20130907054251-c21fe-8364e108e6296c51d604e7b9220f74c06da23924
more optimizations using moves to reduce copies in the network stack

Ignore-this: 65ee07ae383f95207885ba2741dbe17a

darcs-hash:20130907061353-c21fe-99fb1a8b47333619b1c8c60ec0a2c5bb1e59dd7b