There should be a way to enable/disable qml profiling tracing

Real world applications have a lot of bindings, and the QML implemented view in creator can not update quickly enough when there are 10000 elements to destroy and re-create in the MainView.qml for the qmlprofiler plugin. There also needs to be a way to start and stop profiling similar to what is possible in callgrind. The attached patch is my hack to make that possible, but there should be a better way.