Update version number

Author: RemiLehe

LICENSE.txt

@@ -1,4 +1,4 @@
-WarpX v0.1.0 Copyright (c) 2018, The Regents of the University of California, through Lawrence Berkeley National Laboratory, and Lawrence Livermore National Security, LLC, for the operation of Lawrence Livermore National Laboratory (subject to receipt of any required approvals from the U.S. Dept. of Energy). All rights reserved.
+WarpX v18.11 Copyright (c) 2018, The Regents of the University of California, through Lawrence Berkeley National Laboratory, and Lawrence Livermore National Security, LLC, for the operation of Lawrence Livermore National Laboratory (subject to receipt of any required approvals from the U.S. Dept. of Energy). All rights reserved.
 
 
 Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Python/setup.py

@@ -20,7 +20,7 @@
     package_data = {}
 
 setup (name = 'pywarpx',
-       version = '0.1.0',
+       version = '18.11',
        packages = ['pywarpx'],
        package_dir = {'pywarpx':'pywarpx'},
        description = """Wrapper of WarpX""",