Merge pull request #20 from tilowestermann/UnlimitedSteps

Show UIActionSheet for hidden steps #15
Update README.md
Update README.md
Merge branch 'master' into UnlimitedSteps
Bugfix: Don't select a step when the user cancelled the actionSheet
Bugfix:
* disable selecting upcoming steps in UIActionSheet
* don’t show UIActionSheet when touched point could not be identified