✨ Make early access project scope

[12944qwerty]

Summary

Changes the early access behavior to project scope.
Specifying early access when creating one project does not enable early access globally. Must use pros --use-early-access=True to enable early access by default.
Even if early access is enabled by default, you can use PROS 3 with pros c n <name> --no-early-access for that project.

Closes #324

[ayushuk]

Overall, I think this is a good implementation. I'm thinking what if we added a QOL feature where if you are already in a early access project, query-templates returns early access templates. At the moment you have to specify the -ea flag to see them. It isn't a big deal since query-templates is already a command you can run globally but it could create confusion since users would expect the templates in respect to the context of the project. The resolve_templates doesn't already have project info so we would just need to figure out if there's a project.pros in the current directory and read that. This could be something for later or for this PR if you have the chance. Address the comments and we can merge this.

[ayushuk]

LGTM