QmlProfiler: Move the data structs of the V8 model into the model class

QmlProfilerDataModel does it the same way and we don't pollute the
namespace as much like this.

Change-Id: Id1ed2c444cb2556fb8f1c886a754e51f3eae5772
Reviewed-by: Kai Koehne <kai.koehne@digia.com>
QmlProfiler: Clarify interaction when expanding category labels

Change-Id: I22c106b1493ee323c6f8baf92faa0fd543386c9b
Reviewed-by: Kai Koehne <kai.koehne@digia.com>
QmlProfiler: Remove some unused constants and document one that's used.

Change-Id: I279648bd3db01088b6ba198e4c232f15c1310f43
Reviewed-by: Kai Koehne <kai.koehne@digia.com>
ProjectNodes: Move (add|remove|delete|rename)Files to FolderNode

Change-Id: I464a4c1da299d61accba7abf928464ea6ad2ba4c
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
ProjectNodes: Move (add|remove)(File|Folder)Node to FolderNode

The reason they were on ProjectNode is that the signals are emitted
on the projectnode, but since I moved addFiles and others to FolderNode,
this makes more sense.

Change-Id: I918ca4d93dab78c8bb93dff03f53d1a6fbe21340
Reviewed-by: Daniel Teske <daniel.teske@digia.com>