Miscellaneous repo cleanup

- Cleaned up package.json
- Cleaned up bower.json
- Cleaned up wording, fixed broken links, and improved contribution
instructions in README.md
- Removed grunt-cli as a dependency in .travis.yml
FWIW, I wonder if we should try to minimize the amount of documentation / examples we put here in favor of just sending people to the official docs, in order to reduce our maintenance burden.  But I don't feel strongly, and this is definitely fine for now.