Added MANIFEST.in to ensure data files, i.e. materials files for user libraries, etc... are installed with the package.

MANIFEST.in

@@ -0,0 +1,5 @@
+include README.rst
+recursive-include tests *
+recursive-include tools *
+recursive-include user_libs *
+global-exclude *.DS_Store

setup.py

@@ -44,6 +44,8 @@ with open('gprMax/__init__.py', 'r') as fd:
                             fd.read(), re.MULTILINE).group(1)
 
 packages = [packagename, 'tests', 'tools', 'user_libs']
+#packagesdata = {}
+#package_data={'mypkg': ['data/*.dat']},
 
 # Python version
 if sys.version_info[:2] < (3, 4):
@@ -173,4 +175,5 @@ setup(name=packagename,
       ],
       ext_modules=extensions,
       packages=packages,
+      include_package_data=True,
       include_dirs=[np.get_include()])