PacketManipulator - Exception adding a new Sequence

[luis]

When you open PacketManipulator:

1. Select one packet in Protocols Perspective

2. Right click

3. Add to a new sequence

Traceback (most recent call last):
  File "/Users/bastiao/Umit/svn/pm/trunk/umit/pm/gui/tabs/protocolselectortab.py", line 268, in __add_to_new_sequence
    ServiceBus().call('pm.sessions', 'create_edit_session', sel)
NameError: global name 'ServiceBus' is not defined

Missed a import, patch in attachment.

[luis]

Following our IRC conversation:

21:28 < nopper> k0p: 21:28 < nopper> just patch it in trunk

Commited in r5576.