Handful of improvements
- docs(README): update badges b5a0f1a
- chore(package): add main field 1d69d75
- ci: use node12 and latest for testing abada9c
- refactor: remove defaultValue argument from getOrFail method 3d956d1
- refactor: remove _ prefixes from all private properties 1c296a2
- chore: remove tslint in favor of eslint 1c0a1c6
- chore: update dependencies c740f57