0.2.6 - Fix Step Children Not Being Added Properly

This release addresses what are really two major bugs, though both small in terms of complexity. The now-resolved issues:

• Step children would not be reordered every time they were serialized to elements; an invalid order would be kept. I've made a note to test element ordering before 1.0.0.
• If the Step had <visible> child element, we'd try to set that child to its own parent! The silly bugs are the ones that get you.

Full Changelog: 0.2.5...0.2.6