Fix crash cause by wrong ownership

Q_INVOKABLE methods are factory-methods from
QtQuick-pov and Javascript takes over ownership
and deletes the returned instance when the
garbage collector kicks in.

Explicit set the ownership of the SME::StateMachine
to QQmlEngine::CppOwnership to prevent v4 from
deleting the instance.

Change-Id: I423e248bc30df84bc26ee480ea42c91e86a675a2
Reviewed-on: https://codereview.kdab.com/11735
Reviewed-by: Continuous Integration <build@kdab.com>
Reviewed-by: Volker Krause <volker@kdab.com>
Fix Mouse wheel zoom changes position of the state machine item

This solves FOCA-86

Change-Id: I0277d99e0237d186fd18fa64fe79601231f989f2
Reviewed-on: https://codereview.kdab.com/11833
Reviewed-by: Continuous Integration <build@kdab.com>
Reviewed-by: Volker Krause <volker@kdab.com>
Fix Name change of state machine cause change of the window size

This solves FOCA-136

Change-Id: I00c319b92850df255e700023ea1bb38ffdbe04e9
Reviewed-on: https://codereview.kdab.com/11908
Reviewed-by: Continuous Integration <build@kdab.com>
Reviewed-by: Volker Krause <volker@kdab.com>