qa/550 failing on some platforms ... yet another python issue

[Ken McDonell <kenj@xxxxxxxxxxxxxxxx>]

+ Traceback (most recent call last):
+   File "leak-getpdu", line 17, in <module>
+     pcppdu.send_pdu(sock, -1, 1, str("X") * 65000)
+   File "/home/kenj/src/pcp/qa/secure/pcppdu.py", line 469, in send_pdu
+     sock.send(header + data)
+ TypeError: can't concat bytes to str

This is on
vm05        3.10.8   x86_64  Gentoo 2.2
with
kenj@vm05:~/src/pcp/qa$ python --version
Python 3.4.1