py-yajl: new package at 0.3.5 (#14278)

* py-yajl: new package at 0.3.5

* py-yajl: use PyPI mirror

* py-yajl: use short PyPI url

* remove py-ujson package

* py-yajl: remove unused imports

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

+# 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 PyYajl(PythonPackage):
+    """Python bindings for the Yajl JSON encoder/decoder library."""
+
+    homepage = "https://github.com/rtyler/py-yajl"
+    url      = "https://pypi.io/packages/source/y/yajl/yajl-0.3.5.tar.gz"
+
+    version('0.3.5', sha256='432321ea613692a4782a2368a300f57b59c64a3c8508c7465af3fdc045e7bcc2')
+
+    depends_on('py-setuptools', type='build')