Add OCL > Validate Action

This will validate the model, open the validityView and update its content

Change-Id: I0000000000000000000000000000000000000000
Signed-off-by: marwa rostren <mrostren@obeo.fr>
Initialize correctly the ValidityView

When opening the validityView, the serviceSelection is null !
We use the ActiveEditor site and the treeSelection to update the
validityView content.



Change-Id: I91761f499064f5187b5a8a70a4d5696c0540e401
Signed-off-by: marwa rostren <mrostren@obeo.fr>