Fixes scrollToItem in flow mode not being exact: #15
Contains item size averaging logic to better estimate scrollToItem locations in flow layout mode.
We now always add at least 1 of every "type" to the view if in flow layout mode so that we can size them.
Some minor refactoring as well.
Scrolling to an item in flow mode is now instantaneous: #12
New API allows scrolling to positions other than just top #14
Fixes scrollToItem in flow mode not being exact: #15 Contains item size averaging logic to better estimate scrollToItem locations in flow layout mode. We now always add at least 1 of every "type" to the view if in flow layout mode so that we can size them. Some minor refactoring as well. Scrolling to an item in flow mode is now instantaneous: #12 New API allows scrolling to positions other than just top #14