poping up Input fields in Node Editor
Changes to the json format.
Add "id", "name" and "units" to the extraDescriptions
Name changes:  correctDesc -> description and studentSelections -> selections
Merging changes; added addNode() function to given object.
adding input fields to node editior
Merge branch 'master' into megha2

Conflicts:
	www/index.html
Updated model.js
Merge branch 'master' of https://github.com/rptiwari/LaitsV3
More fixing up js/model.js accessor functions.
Now have ability of add methods that are common to
both student and given models.
Fix variable name error.
Finished adding getters to build model.js after changes; additional changes to test code.
Skeleton for function to handle PM repies.
Erased functions that were moved to obj section; fixed setToDemo().
Merge branch 'master' of https://github.com/rptiwari/LaitsV3
Re-do changes to fix model.
Minor changes to pedagogical_module.js.
Revert "Re-do changes to fix model."
But keep the this._ID notation.
This reverts commit 4374bf3ebaced4a84031fab910b45383553e6d5e.

In test harness js/json/object.html, replaced document.write()
        used /* */ for long comments, changed node name to
        not conflict with built in.
Modified addNode to optionally take properties, and removed addNodeObject()

Shortened up the naming convention for node
getters and setters:
        getNodeInputs -> getInputs
        getNodeUnits -> getUnits
        et cetera
Undo switch to new name convention for
getters and setters in js/model.js for node name.
Some small bug fixes so node editor opens.
Replace getNodeNameByID -> getName to match
js/model.js naming convention.
Work on pedagogical module.
Code changes to track interaction among students : Sachin Grover