This tool allows you to check which files in your translation need update. To show the list choose a directory (it doesn't works recursively) or translator.

When you click on the filename you will see plaintext diff showing changes between revisions so you will know what has changed in English version and what informations you need to update.You can also click on [diff] to show colored diff.

Choose a directory:

Or choose a translator:

Good, it seems that all files are up to date for these conditions.