Remove byteorder dependency

[tustvold]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

Parquet currently depends on the byteorder crate, and only uses it in an extremely limited capacity.

Describe the solution you'd like

Much of the byteorder functionality can be found in the standard library, e.g. https://doc.rust-lang.org/std/primitive.u64.html#method.from_le_bytes. We should just use this instead and remove a dependency.

Describe alternatives you've considered

Additional context