Added Try/Except block around header delimiter

Headers should end with a carriage return/line feed at the end of each line and then a blank line (with a CRLF) to end the header. In some cases, for example a 406 reponse, the header will not have the blank line and instead the server will close the connection. In this case the code raises a ValueError exception which is not very helpfully. Inserting this try/except block adds clarity to what failed.

Author: killian441

__pycache__/rtsp.cpython-36.pyc

@@ -180,7 +180,11 @@ def recv_msg(self):
         msg = ''
         if self.cache():
             tmp = self.cache()
-            (msg, tmp) = tmp.split(HEADER_END_STR, 1)
+            try:
+            	(msg, tmp) = tmp.split(HEADER_END_STR, 1)
+            except ValueError as e:
+            	self._callback(self._get_time_str() + '\n' + tmp)
+            	raise RTSPError('Response did not contain double CRLF')
             content_length = self._get_content_length(msg)
             msg += HEADER_END_STR + tmp[:content_length]
             self.set_cache(tmp[content_length:])