Eliminate separate examples crate

[Aposhian]

What problem does this solve or what need does it fill?
The examples crate notes that being a separate crate was a constraint of using Bevy 0.4. Now that we are on Bevy 0.5, can we move the examples into the standard location so you can run cargo run --example at the repository root?

Describe the solution would you like?
Eliminate examples crate and add examples to top level Cargo.toml

Describe the alternative(s) you've considered?
N/A

Additional context
N/A

[joshuajbouw]

This has been fixed by #182