Includes modifications to Tony Buser's Thingiview.js
(https://github.com/tbuser/thingiview.js)
to allow dynamic 3D display of STL file in WISEngineering and WISE4.

This incorporates an estimation activity, where students estimate
attributes (such as side-length, surface area, or volume) of the 
shapes, using a reference.  In this case, the reference is the
woman from Google Sketchup:
http://sketchup.google.com/
who happens to be roughly 5ft,6in tall.  She is included in the
STL file and renders as part of the shape on screen.

The estimation includes a estimate-error-bar, just as is used in
the Estimation Calculator:
http://teacherlink.org/estimate/
This lets students know if an estimate is too high or too low,
and provides an exact value if a student's estimate is close
enough.

This is a step-type, so the entire directory drops into:
$CATALINA_HOME/webapps/vlewrapper/vle/node/
and, with some minor modifications to 
$CATALINA_HOME/webapps/vlewrapper/vle/node/setupNodes.js
to include this path, the new step type will work.
(there are still a few bugs to work out...)

More info on customizeable step types for WISE4 / WISEngineering is here:
https://github.com/WISE-Community/WISE-StepTypeCreator