OTWO-1412 Initializes bzr properly and sets up logger.

If bzr logger is not set, warning messages generated by bzr get
suppressed and an error is logged to stderr instead, telling us
that logger is not initialized.

This was causing bzr Sloc jobs to die or hang in some cases.

Author: amujumdar

lib/scm/adapters/bzrlib/bzrlib_pipe_server.py

@@ -1,8 +1,10 @@
 from bzrlib.branch import Branch
 from bzrlib.revisionspec import RevisionSpec
+from cStringIO import StringIO
 import sys
 import time 
 import traceback
+import logging
 
 class BzrPipeServer:
   def __init__(self, repository_url):
@@ -88,6 +90,9 @@ def command_loop():
 
 if __name__ == "__main__":
   try:
+    stream = StringIO()
+    handler = logging.StreamHandler(stream)
+    logging.getLogger('bzr').addHandler(handler)
     command_loop()
   except:
     exc_trace = traceback.format_exc()