Valgrind: Clean up tools interface a bit

Mainly move tool specific code from plugin.cpp to *tool.cpp.
Clean up includes etc.

Change-Id: Ic968ead9d93099c59abe9f99a9db529305160f95
Reviewed-by: Christian Stenger <christian.stenger@theqtcompany.com>

src/plugins/valgrind/callgrind/callgrinddatamodel.h

@@ -41,7 +41,7 @@ class DataModel : public QAbstractItemModel
     Q_OBJECT
 
 public:
-    explicit DataModel(QObject *parent);
+    DataModel();
     virtual ~DataModel();
 
     virtual void setParseData(const ParseData *data);