freeze pillow and reportlab versions

setup.py

@@ -11,8 +11,8 @@ setup(
         ],
     },
     packages=find_packages(exclude=['tests']),
-    install_requires=["reportlab>=3.4.0",
-                      "Pillow>=4.1.0"],
+    install_requires=["reportlab==3.5.17",
+                      "Pillow==5.3.0"],
     setup_requires=["pytest-runner"],
     tests_require=["pytest", "pytest-flake8", "six"],
     url='http://domtabs.sandflea.org',