first cut at expand/collapse for idref links (only working on objects right now)
some changes to the css stylesheet to get rid of a narrow white vertical bar that showed up to the right of observables in the main table for even rows (those with the shaded gray background).  this was showing up where the object was highlighted with a blue-gray background.

the white bar was between the blue-gray background for the object and the parent table cell (gray background)
changed the fonts back to old behavior

* Arial for the main table
* Lucida for the metadata table

added border below header row and made headers left aligned
now not showing the "id" heading line in the inline expand/collapse

this also fixes the broken idref "links"
now not showing expand/collapse for "external" refids (those not found in current document)
changed how expand/collapse on object_reference is presented (once expand/collapse is re-enabled for related/associated objects, this will apply there too)

instead of being a black bar saying "toggle" the heading is now linked to the toggle action and there is a "+" sign placed at the front of the line via css.

the highlight and jumpt to target has been moved to a separate link at the end of the line.