[update] Added mock as a required package

Author: NoumbissiValere

setup.py

@@ -42,7 +42,8 @@
         # TODO: make optional?
         "paramiko>=2.4.1,<2.5.0",
         "scp>=0.13.0,<0.14.0",
-        "celery>=4.2.0,<4.3.0"
+        "celery>=4.2.0,<4.3.0",
+        "mock==2.0.0"
     ],
     classifiers=[
         'Development Status :: 3 - Alpha',