Fix for a bug where binding enter and exit handlers would cause only one to be triggered.
Merge branch 'master' of github.com:markfinger/viewport
Lots of changes...
- The library's namespace is now `scroll`, formerly it was `viewport`.
- The AMD dependency is now opt-in.
- Underscore is now supported as an alternative to the Lodash dependency.
- The src directory has been compressed into a single JS file.
Merge branch 'master' into gh-pages

Conflicts:
	.gitignore
	tests/scripts/main.js