Move logging functionality into new cmd.Log type

cmd/juju/main.go

 package main
 
 import (
+        "launchpad.net/gnuflag"
         "launchpad.net/juju/go/cmd"
         "os"
+)
+
+// When we import an environment provider implementation
+// here, it will register itself with environs, and hence
+// be available to the juju command.
+import (
+        _ "launchpad.net/juju/go/environs/ec2"
 )
 
 var jujuDoc = `
 juju provides easy, intelligent service orchestration on top of environments
 such as OpenStack, Amazon AWS, or bare metal.
 
 https://juju.ubuntu.com/
 `
 
 // Main registers subcommands for the juju executable, and hands over control
 // to the cmd package. This function is not redundant with main, because it
 // provides an entry point for testing with arbitrary command line arguments.
 func Main(args []string) {
-        juju := cmd.NewLoggingSuperCommand("juju", "", jujuDoc)
+        juju := &cmd.SuperCommand{Name: "juju", Doc: jujuDoc, Log: &cmd.Log{}}
         juju.Register(&BootstrapCommand{})
+        juju.Register(&DestroyCommand{})
         os.Exit(cmd.Main(juju, cmd.DefaultContext(), args[1:]))
 }
 
 func main() {
         Main(os.Args)
 }
+
+func addEnvironFlags(name *string, f *gnuflag.FlagSet) {
+        f.StringVar(name, "e", "", "juju environment to operate in")
+        f.StringVar(name, "environment", "", "")
+}