Fixed typo in ProjectileManager

[RenderBr]

This is a very simple pull request. I have simply bulk renamed the class that was originally ProjectileManagager to ProjectileManager. This is minor, but I felt like it should be done.

[hakusaro]

Won’t this break any third party consumers of the ProjectileManagager?

[drunderscore]

Yeah, this is both source and binary incompatible, can't rename it.
If it bothers you enough, I suppose this will have to do:

using ProjectileManager = ProjectileManagager;

[ghost]

Your very correct, there would have to be a change in all the plugins to support this, as this is hard to do by contacting all the plugin developers I believe that this should go unchanged...

[RenderBr]

Fair enough, I didn't think about this. Feel free to close this PR.

[ghost]

@RenderBr if you wish to close this then close the PR with the close button

[Arthri]

For the record, I'm not against this PR, but it'll have to be delayed until the next major update to prevent unnecessary breaking changes in between feature versions

[ghost]

guess this is a major update thing...