FormWidget: Move aria attributes to this.focusNode.

Handles attributes specified declaratively at widget creation time,
plus set programatically (at any time) via setAttribute().

Also overrides getAttribute(), hasAttribute(), and removeAttribute()
to make it appear that the aria attributes are set on the widget root node.
The abstraction is leaky though because myWidget.attributes will reflect
the true attributes set on the root node.

Fixes #193.
set tag to 0.3.0-alpha
Gruntile: jsdoc config for paths and path format
Gruntfile: jsdoc config with 0.3.0 version number (a bit in advance)
Properly support this.containerNode:

For declarative instantiation, move initial children into this.containerNode.

Also makes appendChild() and insertBefore() work on this.containerNode
rather than widget root node (unless this.containerNode is undefined).
But this only applies after widget creation finishes, because buildRendering()
needs access to the real appendChild() method.

Also, moved all code related to containerNode from delite/Widget to delite/Container.
This means that any widget that contains content (ex: Button) should extend Container
rather than Widget.  Note that the getChildren() method was moved from Widget
to Container.

Finally, made API doc explicit that Container is meant for when the subclass contains children
from the app's point of view, rather than when child nodes / child widgets are used
as an implementation detail..
update dpointer dependency to 0.3.x
Added missing semi-column in test file
update version to 0.3.0, and decor dependency to 0.2.1
Add a fallback location for clean-css module.  Fixes #274.
Leverage require.toUrl function to resolve path to css files.  Fixes #275.
Add warning message when a css file is not found instead of failing silently.
Run tests using Intern 2.1 rather than 1.7.
iOS though not working yet, temporarily disabled.
Also switching to FF 31 and Chrome 36.
Makes delite/css layersMap reference the relative mid of the layer instead of the complete path.
fix API doc for startup()
Prefer attachedCallback() to startup().
Also, make createdCallback() and attachedCallback() automatically chain.
Removes chaining of startup() though, since subclasses generally shouldn't
extend it anyway.

Fixes #287, refs #283, refs #257.
Remove code from emit() to squelch events emitted before startup() call.
Fixes #288.
Remove _onKeyDown() extension point from DialogUnderlay.
User code can just call DialogUnderlay#on("keydown", ...), although in the case of Dialog
it seems easier to just listen for keydown events on <body> or <html> instead.

Also remove dcl.before() advice from destroy() method, since that method
is automatically chained.

Refs #281.
Remove underscore from names of protected properties:

* CustomElement: _created, _attached, _parseAttr --> parseAttribute, _parseFunctionAttr --> parseFunctionAttribute
* HasDropDown: _buttonNode, _arrowWrapperNode, _popupStateNode, _aroundNode
* KeyNav: _onLeftArrow, _onRightArrow, _onUpArrow, _onDownArrow, _getNext
* Widget: _started

Store still needs to be addressed.

Refs #280.
Use eventNameHandler or _eventNameHandler for event handlers.
Fixes #281.

Note that _onFocus/_onBlur/onFocus/onBlur is tracked separately as #214.
remove vestigial code from when scroll bar was on popup wrapper, refs #266.