Dropdowns

Most of this is a direct port of a series of changelists from google that cause us to use html instead of svg for our dropdrowns.  The most noticeably benefit of this is that our dropdowns no longer get cut off by the bottom of the workspace.

The one issue I had to fix was specific to IE.  When creating the menu, we would append a child to the document, and then move it into the correct position.  IE would scroll the window to the added element before doing the reposition.  Fix was to initially set it to hidden.