Change version to 2.0.0-dev.
Migrate from callbacks to promises.
Return all errors via promises. Fix jsDoc.
Switch to browserify browser field in package.json.
Update documentation.
Fix readme.
Fix typo.
Refactoring.
Fix bug in validation.
Add promises fallback.
Change user agent at server.
Update readme.
Add test coverage and coveralls support.
Fix bugs and improve test coverage.
Update coverage badge.
Change version to 2.0.0.
Merge branch 'release/2.0.0'