message: update docs for new contract name
diff: @@ -107,7 +107,7 @@ After installing, navigate to https://remix.ethereum.org/ in the browser of your
  Find the "plugins" tab on the left of the IDE user interface. Select remixd and connect. You will now see the entire net-emissions-token-network folder in the file explorer within remixd.
  -Under localhost -> contracts, select Contract.sol in the file explorer.
  +Under localhost -> contracts, select NetEmissionsTokenNetwork.sol in the file explorer.
  Go to the compiler tab, change the compiler version to 0.6.2, and compile the contract.
  