Substitute post for get. Received 414 error when requesting large poly

query.

http://www.overpass-api.de/command_line.html

http://en.wikipedia.org/wiki/POST_(HTTP)

Author: trypy

overpass/api.py

@@ -83,11 +83,12 @@ def _GetFromOverpass(self, query):
         payload = {"data": query}
 
         try:
-            r = requests.get(
+            r = requests.post(
                 self.endpoint,
-                params=payload,
+                data=payload,
                 timeout=self.timeout
             )
+            
         except requests.exceptions.Timeout:
             raise TimeoutError(self._timeout)