Update tox.ini to be in line with marshmallow

Author: sloria

tox.ini

@@ -30,13 +30,13 @@ commands = sphinx-build docs/ docs/_build {posargs}
 
 ; Below tasks are for development only (not run in CI)
 
-[testenv:watch-docs]
-deps =
-  sphinx-autobuild
+[testenv:docs-serve]
+deps = sphinx-autobuild
 extras = docs
-commands = sphinx-autobuild --open-browser docs/ docs/_build {posargs} --watch src/flask_marshmallow --delay 2
+commands = sphinx-autobuild --port=0 --open-browser --delay=2 docs/ docs/_build {posargs} --watch src --watch CONTRIBUTING.rst --watch README.rst
 
-[testenv:watch-readme]
+[testenv:readme-serve]
 deps = restview
 skip_install = true
 commands = restview README.rst
+