Docs: Add Windows notes, .env section, make formatting consistent, fix typos to CONTRIBUTING.md

[allella]

• I have read Chapter's contributing guidelines.
• My pull request has a descriptive title (not a vague title like Update README.md).
• My pull request targets the master branch of Chapter.

• Adds notes and improved the docs for Windows / Git for Windows / Git Bash users to start addressing Handling symlinks on Windows #465@paizle
• Added a .env Configuration File section and link to it to avoid confusion with .env and .env.example like in Add npm run postinstall to contributing.md #462@NorthDecoder
• Made commands, command line output, and italics text consistent in the various sections
• Fix typos noted in Improve Node, Docker, Postegres and Other Sections of CONTRIBUTING.md #447
• Format "Note:" text consistently
• Made "Prerequisite" software bold and consistent.
• Added better OS-specific notes and links for downloading Git, Docker, and Node.js

Edit(Oliver):
Closes#465
Closes#462

I hope that edit is okay, @allella. I wasn't sure it closed 447, so I left that alone.

[gitpod-io]

[allella]

@paizle and @NorthDecoder I wanted to add you add you as reviewers but GitHub won't let me. I think we figured it's because you haven't already commented on the PR and/or something to do with starring the project or the freeCodeCamp team settings.

In any case, I'd appreciate if you can look at the changes. Viewing it at https://github.com/allella/chapter/blob/docs/windows-contributing/CONTRIBUTING.md is the only sane way to review the changes.

[paizle]

@paizle and @NorthDecoder I wanted to add you add you as reviewers but GitHub won't let me. I think we figured it's because you haven't already commented on the PR and/or something to do with starring the project or the freeCodeCamp team settings.

In any case, I'd appreciate if you can look at the changes. Viewing it at https://github.com/allella/chapter/blob/docs/windows-contributing/CONTRIBUTING.md is the only sane way to review the changes.

The docs look ok to me. As far as I can tell, Git Bash on Windows seems to work fine for me at this point.

[ojeytonwilliams]

This looks good All I found was a single typo.

[allella]

@ojeytonwilliams how about I do a find and replace on yarn to npm in this doc and then you revert your CONTRIBUTING.md, so we can avoid a conflict?

[allella]

@nhcarrigan could you take a look at Contributing Code >> Step 2 - Prepare the Development Environment of my PR for CONTRIBITING.md to see if the Windows related terminal / shell notes look good?

[naomi-lgbt]

That section looks good to me. 🙂

[allella]

@all-contributors add @nhcarrigan@ojeytonwilliams for docs

[allcontributors]

@allella

I've put up a pull request to add @nhcarrigan! 🎉