add a release script

Author: Steven Silvester

RELEASE.md

@@ -0,0 +1,16 @@
+
+To create a release, run the following:
+
+```
+git clean -dfx
+python setup.py sdist
+python setup.py bdist_wheel
+script_version=`python setup.py --version 2>/dev/null`
+git commit -a -m "Release $script_version"
+git tag $script_version
+git push --all
+git push --tags
+pip install twine
+twine check dist/* 
+twine upload dist/*
+```