Make the code a proper module and command

This commit applies several changes in order to turn the
renderer code into a proper python module and command that
can be easily installed using the setuptools module.

Main changes:
- Main executable is named atc
- Use setuptools to install renderer executable
- Improve tests so they can be easily executed by packages
- Update README instructions

Signed-off-by: Luis Araujo <luis.araujo@collabora.co.uk>

setup.py

+###################################################################################
+# setuptools script for atc (Apertis Test Case and Renderer)
+#
+# Copyright (C) 2018
+# Luis Araujo <luis.araujo@collabora.co.uk>
+#
+# This library 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; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# This library 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 GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  US
+###################################################################################
+
+from setuptools import setup, find_packages
+
+setup(
+    name='atc',
+    version='1.0',
+    license='LGPL-2.1+',
+    description='Apertis Test Cases Renderer',
+    author='Luis Araujo',
+    author_email='luis.araujo@collabora.co.uk',
+    url='https://gitlab.apertis.org/tests/apertis-test-cases.git',
+    packages=find_packages(),
+    classifiers = [
+        'Operating System :: OS Independent',
+        'Programming Language :: Python',
+    ],
+    entry_points = {
+        'console_scripts': [
+            'atc = atc_renderer:main'
+        ]
+    },
+    include_package_data=True,
+    install_requires=['PyYaml', 'jinja2'],
+    zip_safe=False,
+)