New package: py-jupyterhub (#10461)

This package depends on both python 3.5+ and node-js which depends on
python 2.7/2.8 to build. Currently it can only be installed if the
node-js package's python dependency is manually removed, so node-js
will build with python found on the system rather than provided by
spack. Upcoming commits may allow spack to reconcile this
automatically.

var/spack/repos/builtin/packages/py-jupyterhub/package.py

@@ -0,0 +1,31 @@
+# Copyright 2013-2019 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack import *
+
+
+class PyJupyterhub(PythonPackage):
+    """Multi-user server for Jupyter notebooks."""
+
+    homepage = "https://pypi.org/project/jupyterhub"
+    url      = "https://pypi.io/packages/source/j/jupyterhub/jupyterhub-0.9.4.tar.gz"
+
+    version('0.9.4',    sha256='86b1cce446d4e8347e26913878858fc8964d103fde19b606fe37ccc5188d629d')
+
+    depends_on('python@3.5:')
+    depends_on('node-js', type=('build', 'run'))
+    depends_on('py-setuptools', type='build')
+    depends_on('py-dateutil', type='run')
+    depends_on('py-jinja2', type='run')
+    depends_on('py-sqlalchemy', type='run')
+    depends_on('py-tornado', type='run')
+    depends_on('py-traitlets', type='run')
+    depends_on('py-alembic', type='run')
+    depends_on('py-mako', type='run')
+    depends_on('py-async-generator', type='run')
+    depends_on('py-jupyter-notebook', type='run')
+    depends_on('py-prometheus-client', type='run')
+    depends_on('py-send2trash', type='run')
+    depends_on('py-requests', type='run')