Set up NUWebots with all required Webots files

[ysims]

This is a change to the way we use the repos, and removes our need to use NUbots/webots. Instead we use the TC's webots fork as a subtree.

• The TC fork of webots has been added as a subtree to the repo
• The .gitmodules file in the webots subtree has been moved out into the NUWebots directory
• Updates the subtree to use our GitHub mirrors for the Webots dependencies downloads
• Our game.json and team_1.json files from NUbots/webots have replaced the ones in the webots subtree
• Our game.json and team_1.json files have been updated for three robots instead of four or five
• Put the NUgus and the Wolfgang proto files into NUgus and Wolfgang folders - done so we can create a symlink to the folder in the Webots official RoboCup project.
• Updates the .gitignore to ignore the symlink that will be created in the RoboCup project proto directory.

Will be merged (I hope 😅) at the same time as NUbots/NUbook#148, which will have updated instructions to work with what's in this PR.

[KipHamiltons]

The build failing like that can be a few things. The POST size might be too large, or the network might have poor latency. If it's bad latency, trying again will probably fix it, but if it doesn't it'll need to be investigated, with the likely fix of changing the max size of the request.

This is based on this SO link