Merge pull request SolidCode#65 from scifuentes/merged_operations

merged  operations for +-*

Author: etjones

solid/objects.py

@@ -168,6 +168,9 @@ class union(OpenSCADObject):
     def __init__(self):
         OpenSCADObject.__init__(self, 'union', {})
 
+    def __add__(self, x):
+        return self.add(x)
+
 
 class intersection(OpenSCADObject):
     '''
@@ -177,6 +180,9 @@ class intersection(OpenSCADObject):
     def __init__(self):
         OpenSCADObject.__init__(self, 'intersection', {})
 
+    def __mul__(self, x):
+        return self.add(x)
+
 
 class difference(OpenSCADObject):
     '''
@@ -185,6 +191,9 @@ class difference(OpenSCADObject):
     def __init__(self):
         OpenSCADObject.__init__(self, 'difference', {})
 
+    def __sub__(self,x):
+        return self.add(x)
+
 
 class hole(OpenSCADObject):
     def __init__(self):