Added minimum version of twine to dev tool requirements in setup.py

Also:
- Updated comment in tasks.py to document minimum version of twine, wheel, and setuptools required

Author: tleonhardt

setup.py

@@ -73,7 +73,7 @@
     # install with 'pip install -e .[dev]'
     'dev': [
         'pytest', 'pytest-cov', 'tox', 'pylint', 'sphinx', 'sphinx-rtd-theme',
-        'sphinx-autobuild','invoke', 'twine',
+        'sphinx-autobuild', 'invoke', 'twine>=1.11',
     ]
 }
 

tasks.py

@@ -1,7 +1,12 @@
 #
 # coding=utf-8
-"""Development related tasks to be run with 'invoke'"""
+"""Development related tasks to be run with 'invoke'.
 
+Make sure you satisfy the following Python module requirements if you are trying to publish a release to PyPI:
+    - twine >= 1.11.0
+    - wheel >= 0.31.0
+    - setuptools >= 39.1.0
+"""
 import os
 import shutil