Cleanup REFERENCE.md

[nbry]

• Remove "Contact Us" instructions for battery_capacity and get_compatibility methods.
• Update exchange_code and exchange_refresh_token descriptions. These methods return Access named tuple (not a dictionary).
• Format all tables.
• Run spell checker through docs and fix typos and grammar.

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Asana: https://app.asana.com/0/1201667141816282/1201694590053125

[nbry]

/rebase

Edit: Fine, Github. I'll rebase locally.

[smartcar-ci]

:tada: This PR is included in version 6.2.0 :tada:

The release is available on GitHub release

Your semantic-release bot :package::rocket: