First attempt at spark-splitter: still not-working
Fix merging artifacts
Reconcile with updated non-Polymer UI
CSS adjustments to make at least the flexbox work
Build version 0.0.10
Fixed a typo/bug + added comments
Fix: icons weren't found without full path
Register event handlers for dragging
Fixed draggability (with bugs still)
Register drag and dragEnd listeners only for the dragging period
Numerous cleanups, refactorings, and fixes.
Remove the unused external CSS

Polymer has a bug that makes using external CSS impossible right now.
Merge branch 'upstream/master'

Conflicts:
	ide/app/manifest.json
	ide/app/spark_polymer.html
Tiny comment fixes
Moved polymer_flex_layout.css import from .html to .css.
Comments
Merge branch 'master'
Merge pull request #211 from ussuri/spark-splitter

Implemented spark-splitter