Better help output for 'triton keys', also avoid double newlines between key output.

lib/do_keys.js

@@ -30,9 +30,11 @@ function do_keys(subcmd, opts, args, callback) {
         if (opts.json) {
             common.jsonStream(keys);
         } else {
-            // pretty print
             keys.forEach(function (key) {
-                console.log(key.key);
+                process.stdout.write(key.key);
+                if (key.key && key.key.slice(-1) !== '\n') {
+                    process.stdout.write('\n');
+                }
             });
         }
         callback();
@@ -52,12 +54,16 @@ do_keys.options = [
     }
 ];
 do_keys.help = (
-    'Show account keys.\n'
+    'Show account SSH keys.\n'
     + '\n'
     + 'Usage:\n'
-    + '     {{name}} keys\n'
+    + '     {{name}} keys [<options>]\n'
     + '\n'
     + '{{options}}'
+    + '\n'
+    + 'By default this lists just the key content for each key -- in other\n'
+    + 'words, content appropriate for a "~/.ssh/authorized_keys" file.\n'
+    + 'Use `triton keys -j` to see all fields.\n'
 );
 
 module.exports = do_keys;