Skip files that were updated after 2018.1

Package alignment had files changed to md. This isn't in the 2018.1 branch.

build.py

     import unity_package_build
     for name in publish_order:
         package_path = os.path.join(sub_package_folders[name])
-        unity_package_build.copy_file_to_project("LICENSE.md", ".", package_path, logger)
-        unity_package_build.copy_file_to_project("CHANGELOG.md", ".", package_path, logger)
+#        unity_package_build.copy_file_to_project("LICENSE.md", ".", package_path, logger)
+#        unity_package_build.copy_file_to_project("CHANGELOG.md", ".", package_path, logger)
 
 def cleanup(logger):
     logger.info("Reverting temporary file changes:")