Move `once` to `timers-ext` project
Update dependencies list
Update package.json
Move main module to root folder
Resolve within function body
On lack of `setTimeout` fallback to null
Consistent callback validation
Microtask resolution via MutationObserver. #1
Add tests for serial calls
Remove Makefile (it's env agnostic package)
Update Travis CI configuration
Update documentation
v0.2.0
Improve description
Use edge version of es5-ext