Update package.json to reference latest xstyle and put-selector
Update CHANGES.md to reflect current progress toward 0.3.1
Further expand upon tree changes (see what I did there)
Fix remaining issue related to tree expansion click handling
Test column plugins upon grid columns reset
Lay groundwork for column.destroy() (to be defined by plugins)
Implement column.destroy for tree plugin
Clean up tree test and column.destroy code a bit
Implement column.destroy for selector plugin
Oops, tree shouldn't risk clobbering column.destroy
Test column reset for editor; partial impl of column.destroy
Refactor a bit to allow editor's column.destroy to clean up better
Clean up an additional handle in editor's column.destroy
Run column.destroy upon grid destruction as well
Update CHANGES.md to reflect addition of column.destroy
Touch-ups to CHANGES.md for 0.3.1
Set innerHTML of expando node within renderExpando instead of after
Selection: safeguard against superfluous removeRow calls
DnD: add getObjectDndType extension point + test
Keyboard: add focus and focusHeader instance methods