Cleanup of doc files.

Fixed xterm.py (and cleanup) to clean up screen sessions.
Cleaned up sshd.py (though interface is still in flux.)
Added 1024-node network example (treenet1024.py).
Added example showing multiple tests on a single network (multitest.py).
Renamed examples to make them easier to type!

examples/linearbandwidth.py

@@ -0,0 +1,51 @@
+#!/usr/bin/python
+
+"""
+Test bandwidth (using iperf) on linear networks of varying size, 
+using both kernel and user datapaths.
+
+Each network looks like:
+
+h0 <-> s0 <-> s1 .. sN <-> h1
+
+Note: by default, the reference controller only supports 16
+switches, so this test WILL NOT WORK unless you have recompiled
+your controller to support a 100 switches (or more.)
+"""
+   
+from mininet import init, LinearNet, iperfTest
+
+def linearBandwidthTest():
+
+   datapaths = [ 'kernel', 'user' ]
+   switchCounts = [ 1, 20, 40, 60, 80, 100 ]
+   results = {}
+
+   for datapath in datapaths:
+      k = datapath == 'kernel'
+      results[ datapath ] = []
+      for switchCount in switchCounts: 
+         print "*** Creating linear network of size", switchCount
+         network = LinearNet( switchCount, k)
+         bandwidth = network.run( iperfTest )
+         results[ datapath ] += [ ( switchCount, bandwidth ) ]
+         
+   for datapath in datapaths:
+      print
+      print "*** Linear network results for", datapath, "datapath:"
+      print
+      result = results[ datapath ]  
+      print "SwitchCount\tiperf Results"
+      for switchCount, bandwidth in result:
+         print switchCount, '\t\t', 
+         print bandwidth[ 0 ], 'server, ', bandwidth[ 1 ], 'client'
+      print
+   print
+      
+if __name__ == '__main__':
+   init()
+   print "*** Running linearBandwidthTest"
+   linearBandwidthTest()
+   exit( 1 )
+
+