Move logic from Polymer elements to plain JS files

[jonnor]

And start of de-Polymerization in the-graph-thumb, ref #314

[jonnor]

Looks like our test is a bit racy, occationally fails on Saucelabs. Probably because the Polymer element is not always ready when the tests start running...

[jonnor]

Before

  431 the-graph-editor/the-graph-editor.html
  222 the-graph-nav/the-graph-nav.html
  462 the-graph/the-graph.html
  293 the-graph-thumb/the-graph-thumb.html
 1408 total

now

  194 the-graph-editor/the-graph-editor.html
  171 the-graph-nav/the-graph-nav.html
  340 the-graph/the-graph.html
  112 the-graph-thumb/the-graph-thumb.html
  817 total

[bergie]