debug-log: added new debug log api and command

cmd/juju/main.go

Index: cmd/juju/main.go 
=== modified file 'cmd/juju/main.go' 
--- cmd/juju/main.go	2014-01-28 04:58:43 +0000 
+++ cmd/juju/main.go	2014-01-30 12:50:13 +0000 
@@ -91,7 +91,7 @@ 
	jujucmd.Register(wrap(&SCPCommand{})) 
	jujucmd.Register(wrap(&SSHCommand{})) 
	jujucmd.Register(wrap(&ResolvedCommand{})) 
-	jujucmd.Register(wrap(&DebugLogCommand{sshCmd: &SSHCommand{}})) 
+	jujucmd.Register(wrap(&DebugLogCommand{})) 
	jujucmd.Register(wrap(&DebugHooksCommand{})) 
 
	// Configuration commands.