Added matplotlib dependency to setup.py

Author: catalin-manciu

setup.py

@@ -9,7 +9,7 @@
     download_url="https://github.com/tobami/codespeed/tags",
     license='GNU Lesser General Public License version 2.1',
     keywords=["benchmarking", "visualization"],
-    install_requires=['django>=1.6,<1.9', 'isodate>=0.4.7,<0.6'],
+    install_requires=['django>=1.6,<1.9', 'isodate>=0.4.7,<0.6', 'matplotlib>=1.4.3'],
     packages=find_packages(exclude=['ez_setup', 'sample_project']),
     description='A web application to monitor and analyze the performance of your code',
     include_package_data=True,