Basics Upgrade
I have upgraded the Basics series to Unity 2020. There were enough differences between 2019 and 2020 to make this necessary. The editor UI changed in multiple places, the package manager is different, performance is different, and uninitialized private fields no longer generate warnings by default. Some remarks were no longer relevant and a few new ones were added. I made a few stylistic code changes, but nothing that would require you to go through the whole series again if you've already done so.
As I went through the whole thing I also got rid of some typos and copy-paste errors that hadn't been caught yet. If you spot any of those anywhere please let me know!
I'm also doing this for the Custom SRP series, but it'll be a while before that one is completed.
