Add package py-pybind11 (#5096)

* py-pybind11 package was missing

* fixed license file

* attempt to fix flake8

* use python3 compatible python detection

var/spack/repos/builtin/packages/py-pybind11/package.py

@@ -0,0 +1,51 @@
+##############################################################################
+# 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 NOTICE and LICENSE files 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 PyPybind11(CMakePackage):
+    """pybind11 -- Seamless operability between C++11 and Python.
+    pybind11 is a lightweight header-only library that exposes C++ types in
+    Python and vice versa, mainly to create Python bindings of existing C++
+    code. Its goals and syntax are similar to the excellent Boost.Python
+    library by David Abrahams: to minimize boilerplate code in traditional
+    extension modules by inferring type information using compile-time
+    introspection."""
+
+    homepage = "https://pybind11.readthedocs.io"
+    url      = "https://github.com/pybind/pybind11/archive/v2.1.0.tar.gz"
+
+    version('2.1.1', '5518988698df937ccee53fb6ba91d12a')
+    version('2.1.0', '3cf07043d677d200720c928569635e12')
+
+    depends_on('py-pytest', type=('build'))
+
+    extends('python')
+
+    def cmake_args(self):
+        args = []
+        args.append('-DPYTHON_EXECUTABLE:FILEPATH=%s'
+                    % self.spec['python'].command.path)
+        return args