Integration test for RPC client against a real reference Nano node

[gak]

For example for the monetary RPC calls there could be a real Nano account held by feeless to be used with real transactions, holding a small amount of Nano. For example:

• Import the feeless key
• Create a new account
• block_create to the new account, a fraction of the feeless balance to the new acount
• process
• Send it back to the feeless account

Other integration tests should be fairly straightforward, many of them can't be verified exactly apart from just making sure the responses have the right fields and types.