Py3: remove uses of unicode()

CompoundFilter2.py

@@ -271,7 +271,7 @@ def ExplodeCompound(feature):
     features_created = []
     for i in range(0, len(sh.childShapes(False,False))):
         cf = makeCompoundFilter(name = 'child')
-        cf.Label = u'Child' + unicode(i)
+        cf.Label = u'Child' + str(i)
         cf.Base = feature
         cf.FilterType = 'specific items'
         cf.items = str(i)

lattice2ArrayFilter.py

@@ -312,7 +312,7 @@ def ExplodeArray(feature):
     features_created = []
     for i in range(len(plms)):
         af = makeArrayFilter(name = 'Placment')
-        af.Label = u'Placement' + unicode(i)
+        af.Label = u'Placement' + str(i)
         af.Base = feature
         af.FilterType = 'specific items'
         af.items = str(i)

lattice2SubLink.py

@@ -239,7 +239,7 @@ def CreateSubLink(object, subnames, looping):
     if looping != 'Single':
         name = object.Name+"_"+"Elements"
     FreeCADGui.doCommand("f = lattice2SubLink.makeSubLink(name = "+repr(name)+")")
-    label = unicode(subnames[0] if len(subnames)==1 else "subelements")  + u" of " + object.Label
+    label = (subnames[0] if len(subnames)==1 else "subelements")  + u" of " + object.Label
     FreeCADGui.doCommand("f.Label = "+repr(label))    
     FreeCADGui.doCommand("f.Object = App.ActiveDocument."+object.Name)
     FreeCADGui.doCommand("f.SubNames = "+repr(subnames))