This commit is a first-pass attempt at adhering to the style guide of
the Awesome List contribution guidelines at
https://github.com/sindresorhus/awesome/blob/master/pull_request_template.md
Specificaly, I have:
* added a succinct description of the project/theme at top of README.
* added the awesome badge on the right side of the list heading.
* titled the table of contents `Contents`.
* moved the `CONTRIBUTING.md` file to the expected filesystem path.
* capitalized the first word of link descriptions, when present.
* added trailing periods to link descriptions, when not present.
* removed the "A" and "An" prepositions from link descriptions.
* removed the Travis CI build status badge.
* matched the heading levels to the style guide's recommendations.
