Repo cleanup to comply with new catapult deploy process

- Added `/dist/` folder to `.gitignore`
- Replaced references to version number with `0.0.0`
- Replaced all-release `CHANGELOG.md` with per-release `changelog.txt`
- Removed `release.sh` script
- Added `npm run travis` command to `package.json` to build the
distribution files before testing
- Updated and corrected things in the README
- Updated README build badge to only show state of `master` branch
- Added header with version number, repo link, and license to all dist
files