[TACHYON-62] Netty

Netty implementation of the data server.

This patch is not done yet.  Its intent is to show the work I have right now for commenting.

This PR should not be merged until performance results come in.
To be more clear.  The Netty code does a null check to see if there is a value.  If and only if there is a value, we set it.  So we default to not defining it, which should cause Netty to use the real default value.