Add Items to ScrollList Dynamically
Formalize ItemMetadata to Predict Maximum Item Size

Formalize the concept of item metadata to include the maximum
width and height of the item sizes. This helps positional calculations
when dynamically injecting items into the ScrollList.
Fix Broken Tests
Add New Unit Tests for Dynamically Added Items
Merge pull request #27 from WebFilings/add_items_to_scroll_list_dynamically

Add Items to Scroll List Dynamically