docs: Update and cleanup READMEs and examples

[jstirnaman]

This PR proposes the following changes for documentation and examples:

• Applies InfluxDB style guidelines to READMEs, branding, grammar, spelling.

• Adds examples for InfluxQL.

• Explains credentials.

• Adds more instruction for running examples.

• [x] Commit messages are conventional

• [x] Sign CLA (if not already signed)

[jstirnaman]

@sanderson Can you take a look?

[jstirnaman]

@jstirnaman thanks for this PR, not the docs looks more cleaner. Thanks again!

LGTM 🚀

Can you merge this? I don't have permission.

[bednar]

@jstirnaman done