Support for Taxii and Indicators

Added support for raw TAXII and nested/composite indicators.
Gracefully draw nested observables inside indicators.  But remove
odd/even and simply show line underneath.

If observable ID is missing, allow configuration of default string in
config.

Added toggles for both a stix package and an indicator description link
next to the title.

This should be the last pull request for a while, unless I am required
to add support for indicator elements such as Kill Chain, Likely
Impact, COA's etc which will eventually go nicely with the
indicator/observable display.

Also added Iran Oil unit test.  Check it out!