Added helpful messages to setup.py for people who try and run the tes…

…ts with the setup.py commands

setup.py

@@ -1,12 +1,51 @@
 #!/usr/bin/env python
-# Licensed under a 3-clause BSD style license - see LICENSE.rst
 
 import os
+import sys
 from setuptools import setup
 
-# NOTE: The configuration for the package, including the name, version, and
-# other information are set in the setup.cfg file. Here we mainly set up
-# setup_requires and install_requires since these are determined
-# programmatically.
+TEST_HELP = """
+Note: running tests is no longer done using 'python setup.py test'. Instead
+you will need to run:
+
+    tox -e test
+
+If you don't already have tox installed, you can install it with:
+
+    pip install tox
+
+If you only want to run part of the test suite, you can also use pytest
+directly with::
+
+    pip install -e .
+    pytest
+
+For more information, see:
+
+  http://docs.astropy.org/en/latest/development/testguide.html#running-tests
+"""
+
+if 'test' in sys.argv:
+    print(TEST_HELP)
+    sys.exit(1)
+
+DOCS_HELP = """
+Note: building the documentation is no longer done using
+'python setup.py build_docs'. Instead you will need to run:
+
+    tox -e build_docs
+
+If you don't already have tox installed, you can install it with:
+
+    pip install tox
+
+For more information, see:
+
+  http://docs.astropy.org/en/latest/install.html#builddocs
+"""
+
+if 'build_docs' in sys.argv or 'build_sphinx' in sys.argv:
+    print(DOCS_HELP)
+    sys.exit(1)
 
 setup(use_scm_version={'write_to': os.path.join('spectral_cube', 'version.py')})