Show: Tempovis stack support

Improvents:
* Allows using several tempovis instances in arbitrary order
* plugin system (SceneDetail), ease of extending
* Mild restore feature - more respect for changes made by user
* workbench switching support
* undo saveable changes for the time of writing a file

Regressions:
* Removed support for pickling (with hopes to reintroduce later)

src/Mod/Show/DepGraphTools.py

@@ -64,25 +64,3 @@ def getAllDependent(feat):
         list_traversing_now = list_to_be_traversed_next
     
     return list_of_deps
-
-def _isContainer(obj):
-    '''isContainer(obj): returns True if obj is an object container, such as 
-    Group, Part, Body. The important characterisic of an object being a 
-    container is visibility nesting.'''
-    
-    if obj.hasChildElement():
-        return True
-    if obj.hasExtension('App::OriginGroupExtension'):
-        return True
-    if obj.hasExtension('App::GroupExtension'):
-        return True
-    if obj.isDerivedFrom('App::Origin'):
-        return True
-    return False
-
-def isContainer(obj):
-    if _isContainer(obj):
-        return True
-    linked = obj.getLinkedObject()
-    return linked and linked!=obj and _isContainer(linked)
-