Add support for parsing C++11 final classes

Such as:

  class X final {};

This no longer gives a syntax error.
This change has introduced one more shift-reduce conflict in the parser.
with a conflict with a C style variable declaration with name final:

  class X final;

resulting in a syntax error (for C++ not C). This is an an unusual style
for C++ code and more typical declarations do work:

  X final;

Closes #672

Examples/test-suite/python/cpp11_final_class_runme.py

@@ -0,0 +1,62 @@
+from cpp11_final_class import *
+
+fc1 = FinalClass1()
+fc1.method1()
+
+fc2 = FinalClass2()
+fc2.method2()
+
+fc3 = FinalClass3()
+fc3.method3()
+
+fc4 = FinalClass4()
+fc4.method4()
+fc4final = cvar.final
+cvar.final.method4()
+
+fc5 = FinalClass5()
+fc5.method5()
+fc5.final_member_var.finalmethod()
+fc5final = fc5.get_final_member()
+fc5final.finalmethod()
+fc5final = fc5.get_final_member2()
+fc5final.finalmethod()
+
+fc6 = FinalClass6()
+fc6.method6()
+fc6.final()
+
+o = override()
+o.omethod();
+
+y = Y()
+fv4 = FinalVar4()
+yy = fv4.final
+
+fv5 = FinalVar5()
+yy = fv5.final
+
+fv6 = FinalVar6()
+yy = fv6.final
+
+fv7 = FinalVar7()
+yy = fv7.final
+
+fv8 = FinalVar8()
+yy = fv8.final
+
+fv9 = FinalVar9()
+yy = fv9.final
+
+fv10 = FinalVar10()
+fv10.a10(y)
+fv10.b10(y)
+
+fe1 = FinalEnum1()
+fe1.enum_in(FinalEnum1.final)
+
+fe2 = FinalEnum2()
+fe2f = fe2.final
+
+s3f = Space3_final()
+s3f.fmethod();

Examples/test-suite/python/final_c_runme.py

@@ -0,0 +1,6 @@
+import final_c
+
+final_c.init()
+f = final_c.cvar.final
+if (f.yval != 123):
+  raise RuntimeError("f.yval fail")