Remove numpy as a mandatory dependency for starting setup.py

Author: ruairif

NEWS

@@ -1,8 +1,13 @@
 Scrapely release notes
 ======================
 
+0.13.1 (2016-12-21)
+-------------------
+
+- Remove numpy as a mandatory import in setup.py
+
 0.13.0 (2016-12-21)
-------------
+-------------------
 
 - Python 3 support;
 - fixed incorrect webpage encoding detection;

setup.py

@@ -3,19 +3,23 @@
 import platform
 from setuptools import setup, find_packages
 from setuptools.extension import Extension
-import numpy as np
 
 
 USE_CYTHON = 'CYTHONIZE' in os.environ
 IS_PYPY = platform.python_implementation() == 'PyPy'
 ext = '.pyx' if USE_CYTHON else '.c'
+try:
+    import numpy as np
+    include_dirs = [np.get_include()]
+except ImportError:
+    include_dirs = []
 extensions = [
     Extension("scrapely._htmlpage",
               ["scrapely/_htmlpage%s" % ext],
-              include_dirs=[np.get_include()]),
+              include_dirs=include_dirs),
     Extension("scrapely.extraction._similarity",
               ["scrapely/extraction/_similarity%s" % ext],
-              include_dirs=[np.get_include()]),
+              include_dirs=include_dirs),
 ]
 if USE_CYTHON and not IS_PYPY:
     from Cython.Build import cythonize