Adjacency Widget sometimes draws incorrect lines in distributed emulation

```
What steps will reproduce the problem?
1. set up a distributed scenario across 3 servers having about 20 routers
2. turn on adjacency widget
3. some of the blue lines drawn are incorrectly pointing to other nodes
messages about skipping some of the routers are printed to the terminal

Some debugging code was added to widget.tcl to log exec responses to a file.
Only the exec messages for fetching the router ID were logged. Some corrupt
exec responses appear in the log file.

a. Tcl not handling multiple responses well?
b. Python not generating good exec responses?
```

Original issue reported on code.google.com by `ahrenh...@gmail.com` on 29 Aug 2012 at 11:00