Change error messages to use errorx for extra context information

refs #2019
Have second user create his own navigable object

fixes #1969
Known issues: If camera is not the highest level object in the userObject, the camera will come in pointing in the wrong direction and the user will only be able to pitch up and down w/ the mouse.  Side to side and key navigation do not work
Fix camera coming in w/ unexpected 90 degree rotation on it

If a camera was a child of the navObject, but not the main navObject, its model and view transforms were not properly separated.  This checkin separates those transforms for all node3s, and fixes a bug where initial transforms were not properly being adopted on initializeProperty
refs #2027
Fix could not move navObject w/ mouse or keys

The three.js objects were auto-updating their matrices from their position and orientation values, overwriting the matrix that we had set.
refs #2027
Fix bug where user could not navigate w/ mouse keys

We were not always updating the three.js world matrix of the navigation object (and therefore, its children were not getting updated)
refs #2027