Fix Python 3 inconsistency handling -ve numbers for unsigned C types.

An OverFlow error is now consistently thrown instead of a TypeError.

Fixes primitive_types testcase for Python 3

Examples/test-suite/python/primitive_types_runme.py

@@ -275,10 +275,22 @@ try:
 except TypeError:
   if a != t.var_char:
     error = 1
-  pass 
+  pass
 if error:
   raise RuntimeError, "bad char typemap"
 
+try:
+  error = 0
+  a = t.var_ushort
+  t.var_ushort = -1
+  error = 1
+except OverflowError:
+  if a != t.var_ushort:
+    error = 1
+  pass
+if error:
+  raise RuntimeError, "bad ushort typemap"
+
 try:
   error = 0
   a = t.var_uint
@@ -287,10 +299,34 @@ try:
 except OverflowError:
   if a != t.var_uint:
     error = 1
-  pass 
+  pass
 if error:
   raise RuntimeError, "bad uint typemap"
 
+try:
+  error = 0
+  a = t.var_sizet
+  t.var_sizet = -1
+  error = 1
+except OverflowError:
+  if a != t.var_sizet:
+    error = 1
+  pass
+if error:
+  raise RuntimeError, "bad sizet typemap"
+
+try:
+  error = 0
+  a = t.var_ulong
+  t.var_ulong = -1
+  error = 1
+except OverflowError:
+  if a != t.var_ulong:
+    error = 1
+  pass
+if error:
+  raise RuntimeError, "bad ulong typemap"
+
 #
 #
 try:
@@ -301,7 +337,7 @@ try:
 except TypeError:
   if a != t.var_namet:
     error = 1
-  pass 
+  pass
 if error:
   raise RuntimeError, "bad namet typemap"