Builder: Improve column add/remove APIs and add 2 by default
Builder style fixes

* Fix legend color in IE
* Clean up tab styles and fix column editor in Safari (add nib/vendor)
* Resolve scrolling issues in control panel
  * Use dgrid-autoheight and SingleQuery mixin for the column/feature grids
  * Simplify CSS
  * Remove transform/transition for now since it complicates scrollHeight
    issues in column grid
Builder: Add styles for modal About dialog

Signed-off-by: Torrey Rice <rice@sitepen.com>
Builder: Improve some form styles

Signed-off-by: Torrey Rice <rice@sitepen.com>
Rename dgrid Builder to Laboratory
Final Laboratory tweaks for 0.4.0

* Make preview grid and code textarea fit the viewport
* Disable textarea resizing
* Clean up some styles / DOM
* Refine DnD overrides for preview grid to not interfere with ColumnReorder
dTuned demo: Fix dstore API usage to expect promises
README: Add StackOverflow to support section
Grid: Add deprecation warning for column.init/destroy
_StoreMixin: Add debug messages for common migration mishaps
ColumnReorder: Fix logic when event is canceled
Docs: Simplify widget cleanup example after removal of IE<8 code
Selector: Fix regression in Selector/Selection sync with ColumnSets
Tree test page: Fix child filtering and sync API invocations
Fix issues in OnDemand.html test page

* Remove obsolete resetQuery test
* Remove obsolete 'query' parameters
Update dstore version in bower.json