Add Readme section for editor setup

[Danl2620]

This PR edits readme.md and:

• Adds a "Getting Started" section with information about setting up VS Code and Sublime Text.
• Fixes a few of the markdown linter suggestions. The linter wanted all code sections marked with language but I didn't do that for the Wiz examples.
• Removes trailing whitespace.

Feedback welcome!

(also fixes #100)

[Bananattack]

Everything here looks good! Thanks for making your Visual Studio Code extension, and updating the readme docs to add this!

Regarding the linting stuff: It's too bad that bare URLs aren't supported in standard markdown, only GitHub-flavored. ^^; It makes the "raw text" view a little less easy to select in to a clipboard. But yeah, if it's more conventional to use <>-wrapped URLs, we can do this!

The trailing whitespace cleanup + using the syntax tags are good improvements. (If Wiz had syntax highlighting on GitHub, I guess we could use ```wiz ...```, but not sure that they'd offer that for a smaller/less-adopted language? I wonder what that would take!)