BPY Support for Deform Parenting and Vertex Parenting

This adds two new method to the BPY Object type:
 - makeParentDeform
 - makeParentVertex

Both are based on makeParent. In fact, I splitted off the parenting
part of makeParent into an internal function so that all can reuse it. I
also added DEP_graph refresh flag that where missing.

makeParentDeform sets the parent type accordingly for correct
deformation (armature and curve) and checks if the parent and childs are of the
correct type for deformation.

makeParentVertex takes as additional mandatory argument a tuple of
indices to tell the parent which vertex to use. It does some object type
checking too.

Also included documentation. :)

Test file is in the patch there: http://projects.blender.org/tracker/?func=detail&atid=127&aid=2833&group_id=9

Note to Ton: When doing vertex parenting, the dashed parent line is only updated correctly if the objects are on screen when calling the function. If they aren't, the line is wrong and is only corrected when another recalc is called on the parent or child.

source/blender/python/api2_2x/doc/Object.py

@@ -429,8 +429,54 @@ class Object:
     """
     Makes the object the parent of the objects provided in the argument which
     must be a list of valid Objects.
-    @type objects: Blender Object
-    @param objects: A Blender Object.
+    @type objects: Sequence of Blender Object
+    @param objects: The Childs of the parent
+    @type noninverse: Integer
+    @param noninverse:
+        0 - make parent with inverse
+        1 - make parent without inverse
+    @type fast: Integer
+    @param fast:
+        0 - update scene hierarchy automatically
+        1 - don't update scene hierarchy (faster). In this case, you must
+        explicitely update the Scene hierarchy.
+    @warn: objects must first be linked to a scene before they can become
+        parents of other objects.  Calling this makeParent method for an
+        unlinked object will result in an error.
+    """
+	
+  def makeParentDeform(objects, noninverse = 0, fast = 0):
+    """
+    Makes the object the deformation parent of the objects provided in the argument
+    which must be a list of valid Objects.
+    The parent object must be a Curve or Armature.
+    @type objects: Sequence of Blender Object
+    @param objects: The Childs of the parent
+    @type noninverse: Integer
+    @param noninverse:
+        0 - make parent with inverse
+        1 - make parent without inverse
+    @type fast: Integer
+    @param fast:
+        0 - update scene hierarchy automatically
+        1 - don't update scene hierarchy (faster). In this case, you must
+        explicitely update the Scene hierarchy.
+    @warn: objects must first be linked to a scene before they can become
+        parents of other objects.  Calling this makeParent method for an
+        unlinked object will result in an error.
+    @warn: child objects must be of mesh type to deform correctly. Other object
+        types will fall back to normal parenting silently.
+    """
+	
+  def makeParentVertex(objects, indices, noninverse = 0, fast = 0):
+    """
+    Makes the object the vertex parent of the objects provided in the argument
+    which must be a list of valid Objects.
+    The parent object must be a Mesh, Curve or Surface.
+    @type objects: Sequence of Blender Object
+    @param objects: The Childs of the parent
+    @type indices: Tuple of Integers
+    @param indices: The indices of the vertice you want to parent to (1 or 3)
     @type noninverse: Integer
     @param noninverse:
         0 - make parent with inverse