Fix automated builds

[nathanruiz]

To get the builds working again, I've made the following changes:

• Tagged the current bevy commit in https://github.com/Lea-fish/bevy, and switched over to that repo in Cargo.toml.
• Removed the define_blocks macro since it was causing builds to run out of memory. Now the Block enum is built by generate_blocks.
• Updated cargo packages.
• Fixed formatting and clippy warnings in code written since builds started failing.