Create a Contributing Guidelines Document

[battila7]

Brief

To make the project more approachable for others, we should create a CONTRIBUTING.md document.

Task

Create a CONTRIBUTING.md document which contains the following information:

• The kind of accepted contributions and how to submit them.
• Coding style, branching guide, commit message style guide.
• How to build and test the project.

Resources

The following links contain useful guidance:

• Setting Guidelines for Repository Contributors,
• Writing Your Contributing Guidelines.

A recently created one:

• underdocs Contributing Guidelines.