Improved getblocks logging.
Add net2 debug option
Correct logic so that not both lines are displayed

e.g.:-
2014-02-25 06:56:39 received getdata (1 invsz)
2014-02-25 06:56:39 received getdata for: tx 8e2e08d1d851eb1ac800e814796dd7b86fd6d3a8fad41d5bdcb873ac6f4aba8d
Show only one zero instead of many when getblocks request received with a hashStop of uint256(0)
Increase max outbound connections from 8 to 128.
Max blocks in transit set to 16
Allow peers to determine how much they are seen to be misbehaving.

This can allow peers in future to modify their behaviour to avoid netsplits.
Add CaughtUp() function (needed by later commits)
Don't request blocks when block invs received unless it's the syncnode, or we've CaughtUp()
Better logging of ProcessMessages() progress
Show downloaded block size and time taken to download.
Replacement stalled block logic. Depending on the situation, it will either disconnect
the peer (as previous behaviour), or it will reselect a syncnode (e.g. when 500 blocks
have been received from the syncnode).
Allow nodes to send version messages more than once.
Report ping times at they arrive.
Antisocial (needs CaughtUp)
indentation
Rename MarkBlockAsReceived to MarkBlockAsRequested to reduce confusion.
Force selection of a new syncnode since the current syncnode is about to stop sending blocks.
Display unknown commands received.