Contributing: general guidelines

[StackScribe]

Transcribe "Guidelines for contributing" from docs/CONTRIBUTING.md.

Delete this content from the docs/CONTRIBUTING.md file and add a link to this page from both the software and docs CONTRIBUTING.md files.

Part of #972

[YashPimple]

@StackScribe I came across this issue and had some doubts in this issue we need to remove the "Guidelines for contributing" from docs/CONTRIBUTING.md and further need to add links to it So over here I am unable to understand the second part of where we need to "add a link to this page from both the software and docs CONTRIBUTING.md files" can you please elaborate on it so that I can be able to help to resolve it.