docs: Update the documentation for the repo.

What was the problem/requirement? (What/Why)

Our documentation for this repo was not good enough for easy onboarding for customers.

What was the solution? (How)

Hence, updated the documentation accordingly. This PR is inspired mostly from a similar change in the Maya Github repo for deadline cloud : https://github.com/aws-deadline/deadline-cloud-for-maya/pull/173

This also adds submitter installation instructions for Mac OS. https://github.com/aws-deadline/deadline-cloud-for-cinema-4d/issues/61

What is the impact of this change?

Better onboarding steps for customers. Mainly moved the contents of DEVELOPMENT.md to README.md as customers onboarding shouldn't have to deep dive into the DEVELOPMENT.md page.

We will update DEVELOPMENT page in a follow up PR but for now we want to make the README page with clear instructions to follow.

How was this change tested?

This was based off of my personal notes that helped me onboard to Cinema 4D easily.

Was this change documented?

Yes

Is this a breaking change?

No

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aws-deadline / deadline-cloud-for-cinema-4d