changed mode numbers for pong and surround

[benblack769]

This fixes the surround and pong game modes to align with the manual, as per discussion here #366.

[JesseFarebro]

@weepingwillowben do you have any sense of how aligned other modes are with their manual, i.e., 1-indexed with the proper indices?

[benblack769]

@JesseFarebro
My understanding is that most of the environments are currently 0 indexed, even though the manual is 1 indexed. Pong is an example of this. Pong is important to us because there are so many interesting multi-player modes in it.

A few were indexed in more bizarre manners, for example Surround's modes currently start at -1. Some of those were fixed by #365.

Then there are a few environments that do have modes in ALE, but not in the game manual, such as double dunk.