setup.py: Raise Exception on unsupported platforms

setup.py

@@ -21,6 +21,12 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+import sys
+
+if (sys.version_info[0] == 2 and sys.version_info[1] < 7) or \
+   (sys.version_info[1] == 3 and sys.version_info[1] < 2):
+    raise Exception('mwparserfromhell needs Python 2.7+ or 3.2+')
+
 from setuptools import setup, find_packages, Extension
 
 from mwparserfromhell import __version__