Added a new class: TaskDlgFeatureBased which currently contains common
code for TaskDlgSketcherBasedParameters::reject() as well as the same
methode for TaskDlgDressUpParameters.
It's likely that other Feature task dialogs will inherit this class too.
* remove an error message if adding a sketchbased feature without a body
* add champfer or fillet old workflow support
Also rework finishFeature() so at least champfer and fillet may be
inserted into any place of any apropriate body(not only the active one) of the body.
