QtIFW

Simplify registration of objects into script engine

Rename addQObjectChildren, removeQObjectChildren methods to
addToGlobalObject, removeToGlobalObject, and merge the augmentation
of the properties with newQObject.

Also, don't recursively register all objects with their objectNames
in the global scope. This avoids name pollution.

Change-Id: I28f1bc67e6febecc7b5142982c918432b61ed96f
Reviewed-by: Niels Weber <niels.weber@theqtcompany.com>