We have some redundant code so that the viewer can communicate with both the simularium-engine and octopus. Once we've fully transitioned to octopus, we can strip out simularium-engine specific code. This includes the following:
[x] remove the octopus CLI flag and the useOctopus boolean flag, and remove any code that would only be reached when those flags are fals
[x] simplify the logic for receiving frame data from net connection, since octopus will always only send one frame at a time
What needs to happen?