add dev notes

dev.md

@@ -0,0 +1,15 @@
+Steps to publish to PyPI:
+
+1) run `make test`
+2) update version in setup.py
+3) Tag the current release in git to match the version in setup.py
+    git tag -a 1.2.0 -m 'Release 1.2.0'
+4) commit any pending changes to git
+    git add .
+    git commit -m 'commit changes'
+    git push origin 1.2.0
+5) test publish
+    ./publish.sh test
+6) publish to PyPI
+    ./publish.sh pypi
+