roughly working version of normalization stylesheet.

this does two things:
1. creates a reference sequence of all elements with ids and the contents of
   those elements extends down only to the next element with an id or idref.
   within these templates, any nested elements with an id are changed to be
   references using an idref attribute

2. create a reference copy of the source document that replaces all
   occurrences of elements with ids with a reference using an idref
   attribute.

(the actual stylesheet logic is a little more complicated because it has
to distinguish between "top level" elements and nested elements.  the
former are main element in the reference and need to keep their ids. the
nested elements should have their ids replaced with idrefs and child nodes
are lopped off.)
added "normalize test" stylesheet that calls the normalize stylesheet then applies a template to the output of the transformed content (chained stylesheets to normal content and then format for output).  This is a simple test case to prove this works.

Next up, updating the main stix stylesheet for this normalized content.
basic stix stylesheet is working -- printing the main observables table (ids and types only).

next up: need to spit out the html from the "reference" sequence that will produce html that will populate the javascript pristineObjects[] array.
now using toggle() and classes for main obserables table expand/collapse

(no content in the content div yet)
now producing the html for "reference" (the lookup table of template items with their ids)
expanding is now working correctly (on observables) and only adding the reference's body content (not the heading)
fixed small bug that prevented observable types from being properly calculated.