Minor Improvements + Bugfixes

This release has a number of minor improvements:

• The datasource on a Renderer can now be changed.
• BarRenderers now behave properly when given non-unique values
• Axis positioning updates proplery (#420)
• The API surface area has been cleaned and reduced (#447)
• OrdinalScales broadcast when rangeType changes
• Axes have default orientations (#204)
• The bower.json file has been improved (#467)
• The RenderController now exposes a method called flush() which flushes the queue and synchronously renders everything
• The Component.resize call now actually resizes the SVG
• Table._removeComponent is now implemented