Cleaned up the debug output a little.
Introduced some debug levels
so you can decide (roughly) what output you want to see. Level 1
shows command execution, connect and disconnect. Level 2 includes
Level 1 and also shows the RPC callbacks as they happen. Level 3
includes 1 and 2 and also shows when Ruby garbage collection takes
place.
Converted all the simple methods of the form P4#meth( arg ) to
aliases for P4#meth=. Added P4#debug= to complete the scheme. The
P4#meth( arg ) forms are now deprecated. i.e. you should use: