BIM: Fix imports of Python importers

src/Mod/BIM/ArchCommands.py

@@ -608,7 +608,7 @@ def removeCurves(shape,dae=False,tolerance=5):
     with faceted segments. If dae is True, DAE triangulation options are used'''
     import Mesh
     if dae:
-        import importDAE
+        from importers import importDAE
         t = importDAE.triangulate(shape.cleaned())
     else:
         t = shape.cleaned().tessellate(tolerance)

src/Mod/BIM/OfflineRenderingUtils.py

@@ -66,17 +66,17 @@ camera = OfflineRenderingUtils.getCamera(freecadFile)
 
 # export to OBJ
 
-import importOBJ
+from importers import importOBJ
 importOBJ.export(doc.Objects,baseFileName+".obj",colors=colors)
 
 # export to DAE
 
-import importDAE
+from importers import importDAE
 importDAE.export(doc.Objects,baseFileName+".dae",colors=colors)
 
 # export to IFC
 
-import importIFC
+from importers import importIFC
 importIFC.export(doc.Objects,baseFileName+".ifc",colors=colors)
 
 # export to STEP

src/Mod/BIM/bimcommands/BimIfcExplorer.py

@@ -252,7 +252,7 @@ class BIM_IfcExplorer:
     def insert(self):
         "inserts selected objects in the active document"
 
-        import importIFC
+        from importers import importIFC
         from PySide import QtCore, QtGui
 
         doc = FreeCAD.ActiveDocument

src/Mod/BIM/bimcommands/BimLibrary.py

@@ -588,7 +588,7 @@ class BIM_Library_TaskPanel:
 
             todo.delay(self.reject, None)
         elif ext == ".ifc":
-            import importIFC
+            from importers import importIFC
 
             importIFC.ZOOMOUT = False
             importIFC.insert(path, FreeCAD.ActiveDocument.Name)