Exported Symbols test

Do note that anything with an underscore `_` is considered internal, not an API, and subject to change without notice, unless specifically promised otherwise.

dygraphs exports these symbols into the global namespace:

It exports these symbols inside each of those symbols and `Dygraph.{Circles,Plugins,prototype}`:

Loading extras:

New top-level elements after loading extras:

New second-level and `Dygraph.{Circles,Plugins,prototype}` elements after loading extras:

The following surface can be reached via the “require” system. Most of this is considered internal and possibe subject to change at few or no notice even if not, in ipso, underscore-tagged.