Please add important documents

[michalpelka]

I would propose adding essential:

• clang-format file (e.g. https://github.com/o3de/o3de/blob/development/.clang-format) and accept ONLY formatted code.
• code of conduct (https://github.com/o3de/o3de/blob/development/CODE_OF_CONDUCT.md)
• guidelines on contribution (branching, release strategy)

Also:

• PR template
• Issue template.

Also PRs and issues containing code without explanations, spelling errors should be closed if authors fails to correct them.
I know that is not development work, but that is how professionally maintained oss projects are organized.