Fix module.__file__ checks to work on pypy

Note that on pypy, SOABI tags start with '.pypy' which contains
the string '.py'...

tests/build/cythonize_script.srctree

 '''
 PYTHON -m Cython.Build.Cythonize -i '**/*_test.py'
-PYTHON -c "import cy_test; assert cy_test.TEST == 'cy_test', cy_test.TEST; assert '.py' not in cy_test.__file__, cy_test.__file__"
-PYTHON -c "import pkg.cy_test; assert pkg.cy_test.TEST == 'pkg.cy_test', pkg.cy_test.TEST; assert '.py' not in pkg.cy_test.__file__, pkg.cy_test.__file__"
-PYTHON -c "import pkg.sub.cy_test; assert pkg.sub.cy_test.TEST == 'pkg.sub.cy_test', pkg.sub.cy_test.TEST; assert '.py' not in pkg.sub.cy_test.__file__, pkg.cy_test.__file__"
+PYTHON -c "import cy_test; assert cy_test.TEST == 'cy_test', cy_test.TEST; assert not cy_test.__file__.rstrip('oc').endswith('.py'), cy_test.__file__"
+PYTHON -c "import pkg.cy_test; assert pkg.cy_test.TEST == 'pkg.cy_test', pkg.cy_test.TEST; assert not pkg.cy_test.__file__.rstrip('oc').endswith('.py'), pkg.cy_test.__file__"
+PYTHON -c "import pkg.sub.cy_test; assert pkg.sub.cy_test.TEST == 'pkg.sub.cy_test', pkg.sub.cy_test.TEST; assert not pkg.sub.cy_test.__file__.rstrip('oc').endswith('.py'), pkg.cy_test.__file__"
 '''
 
 ######## cy_test.py ########

tests/build/cythonize_script_package.srctree

@@ -11,7 +11,7 @@ if sys.version_info[0] < 3 or sys.version_info >= (3,3):
     # __init__.py compilation isn't supported in Py 3.[012]
     import pkg.sub.test
     assert pkg.sub.test.TEST == 'pkg.sub.test'
-    assert '.py' not in pkg.sub.test.__file__
+    assert not pkg.sub.test.__file__.rstrip('oc').endswith('.py')
 
 ######## test.py ########
 

tests/build/package_compilation.srctree

 PYTHON setup.py build_ext --inplace
-PYTHON -c "import toppkg; assert '.py' not in toppkg.__file__; assert toppkg.PACKAGE == 1"
-PYTHON -c "import toppkg.subpkg; assert '.py' not in toppkg.__file__; assert '.py' not in toppkg.subpkg.__file__; assert toppkg.subpkg.PACKAGE == 2"
+PYTHON -c "import toppkg; assert not toppkg.__file__.rstrip('oc').endswith('.py'); assert toppkg.PACKAGE == 1"
+PYTHON -c "import toppkg.subpkg; assert not toppkg.__file__.rstrip('oc').endswith('.py'); assert not toppkg.subpkg.__file__.rstrip('oc').endswith('.py'); assert toppkg.subpkg.PACKAGE == 2"
 PYTHON -c "import toppkg.a; assert toppkg.a.MODULE == 'a'"
 PYTHON -c "from toppkg.subpkg import a; assert a.MODULE == 'subpkg.a'"