Document component and layout aliases, and add aliases for ModelView and CollectionView.
Change basic styling header background for Panel and Window.
Add initial files for TabPanel implementation.
Simplify Text field and its `emptyText` functionality by removing the "Behavior" classes and implementing a simple hybrid of the previous "empty text" and "infield label" behavior. The empty text is now a separate element that sits on top of the text field, and is shown when the field is empty and doesn't have focus.

Also fix issue with the left label element of the field taking up space even when there was none.
Refactor Panel to use a separate Header class instead of a simple Container for its header.
Add `removeAt()` method to Container.
Change Viewport to not set its own width. Will let browser manage width.
Change `autoSize` config in Card layout to be the inverse: the `fit` config.

Also have the Card layout fire its 'cardchange' event when its parent container is not yet rendered, and fire that event with the previously shown card (if any).
Update doc comment in Column layout.
Give Panel's `title` config a default of empty string.
Fully implement TabPanel.
Merge branch 'TabPanel'
Merge branch 'master' of github.com:gregjacobs/jQuery-Component

Conflicts:
	src/js/Component.js