Disable libasyncns usage in Gajim

libasyncs creates several threads and lets them all block in recv() on a unix
socket. Due to a kernel bug (RHBZ#529202) they go into uninterruptible sleep
for a long time, causing inflated loadavg measurements and scary warnings from
the hung task watchdog in dmesg.

Thankfully libasyncns is not essential for Gajim to work.

 -- Michal

Index: gajim-0.14/src/common/resolver.py
===================================================================
--- gajim-0.14.orig/src/common/resolver.py
+++ gajim-0.14/src/common/resolver.py
@@ -39,7 +39,7 @@ ns_type_pattern = re.compile('^[a-z]+$')
 host_pattern = re.compile('^[a-z0-9\-._]*[a-z0-9]\.[a-z]{2,}$')
 
 try:
-    #raise ImportError("Manually disabled libasync")
+    raise ImportError("Manually disabled libasync")
     import libasyncns
     USE_LIBASYNCNS = True
     log.info("libasyncns-python loaded")