add files to pbtool

Author: Daniel

pb_tool.cfg

@@ -60,7 +60,7 @@ compiled_ui_files:
 resource_files: 
 
 # Other files required for the plugin
-extras: metadata.txt 
+extras: metadata.txt README.md LICENSE
 
 # Other directories to be deployed with the plugin.
 # These must be subdirectories under the plugin directory