[ ] I have not included any built dist files (us maintainers do that prior to a new release)
[ ] I have added tests covering my changes
[ ] All new and existing tests pass
[ ] My changes required the documentation to be updated
 [ ] I have updated the documentation accordingly
 [ ] I have updated the TypeScript 1.8 type definitions accordingly
 [ ] I have updated the TypeScript 2.0+ type definitions accordingly