bitbake/bitbake-layers: fix to run with recent changes

This patch marks the bitbake-layers script as executable and fixes the
instantiation of the BBCooker to match recent changes in the BitBake
libraries.

I've also added a brief header which demonstrates the intent and usage
as taken from Chris Larson's original commit message.

Note: this fix is not upstreamable, it's only required in Poky because of an
outstanding difference between BitBake master and Poky's BitBake.

Signed-off-by: Joshua Lock <josh@linux.intel.com>

bitbake/bin/bitbake-layers

@@ -1,5 +1,11 @@
 #!/usr/bin/env python
 
+# This script has subcommands which operate against your bitbake layers, either
+# displaying useful information, or acting against them.
+# Currently, it only provides a show_appends command, which shows you what
+# bbappends are in effect, and warns you if you have appends which are not being
+# utilized.
+
 import cmd
 import logging
 import os.path
@@ -13,6 +19,7 @@ import bb.cache
 import bb.cooker
 import bb.providers
 from bb.cooker import state
+from bb.server import none
 
 
 logger = logging.getLogger('BitBake')
@@ -38,14 +45,11 @@ class Commands(cmd.Cmd):
         self.returncode = 0
         self.config = Config(parse_only=True)
         self.cooker = bb.cooker.BBCooker(self.config,
-                                         self.register_idle_function)
+                                         bb.server.none)
         self.config_data = self.cooker.configuration.data
         bb.providers.logger.setLevel(logging.ERROR)
         self.prepare_cooker()
 
-    def register_idle_function(self, function, data):
-        pass
-
     def prepare_cooker(self):
         sys.stderr.write("Parsing recipes..")
         logger.setLevel(logging.ERROR)