Upgrade to C# 7.2

[james7132]

With the Unity Incremental Compiler package, supposedly generally available come Unity 2018.3, the C# features up until C# 7.2 will be available. The main offering that this improves on is the use of ref returns and ref locals which will make processing the player state data in the game simulation much more efficient with how it manages memory, potentially offering significant performance gains.

There was a preivous attempt at using the Incremental Compiler and it worked locally; however, CI builds in Unity Cloud Build seems to have broken because of it. We'll have to see if these issues are fixed in the future as these features come online.

[james7132]

On the 2018.2-csharp7.2 branch, we have a version working, and all the tests are passing. The compilation times are much much longer and some of the utilities are still not there. Waiting for the rest of the update to 2018.3 before integrating into the game.

[james7132]

This is tentatively being done as a part of the Unity 2018.3 update. It seems to work better, but the longer compilation times are still there.

[james7132]

This is more or less complete with the 2018.3 update. Marking this complete, and moving the rest of the process to #303.