Beta release of v3.0.0-beta.17

Changes:

• Add bin-linear and bin-ordinal scales for handling binned data.
• Add sequence expression function (analogous to d3.range).
• Add deploy script for publishing Vega schema.
• Fix DOM element binding input reset bug.
• Fix subtle layout issues by having Bound transform always re-compute group bounds.
• Fix internal axis range calculation bug.
• Update autosize parameter to also accept object values ("autosize": {"type": "fit"})
• Add resize property to autosize objects to enable repeated automatic layout. Normally automatic layout is only performed upon initialization or when the width or height signal is modified. This leads to a more stable layout across other changes, which is typically the desired behavior. However, in some cases one might wish to re-size the view on all changes. To enable this behavior use "autosize": {"type": "...", "resize": true}.