Py ase (#4517)

* py-ase: Adding python package py-ase.

* py-ase: Adding Python package py-ase.

* py-ase: Shortened package description.

* py-ase: Splitting package description to multiple lines to avoid char count max.

* py-ase: Removing trailing whitespace. Local flake8 tests passed now that flake8 is working for me.

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

+##############################################################################
+# Copyright (c) 2013-2016, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License (as
+# published by the Free Software Foundation) version 2.1, February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack import *
+
+
+class PyAse(PythonPackage):
+    """The Atomic Simulation Environment (ASE) is a set of tools
+    and Python modules for setting up, manipulating, running,
+    visualizing and analyzing atomistic simulations."""
+
+    homepage = "https://wiki.fysik.dtu.dk/ase/"
+    url      = "https://pypi.io/packages/source/a/ase/ase-3.13.0.tar.gz"
+
+    version('3.13.0', 'e946a0addc5b61e5e2e75857e0f99b89')
+
+    depends_on('python@2.6:')
+    depends_on('py-numpy', type=('build', 'run'))