This patch drops RUBY as a compile time option. Instead the PROTOCOL option
is used to figure out whether or not to build Ruby. If the specified protocol
is 'None', then Ruby is not compiled.
The tester code is in testers/networktest.
The tester can be invoked by configs/example/ruby_network_test.py.
A dummy coherence protocol called Network_test is also addded for network-only simulations and testing. The protocol takes in messages from the tester and just pushes them into the network in the appropriate vnet, without storing any state.