add readme for locales

inc/locale/README.md

@@ -0,0 +1,6 @@
+Please use this interface to submit new translations:
+
+https://www.transifex.com/projects/p/tinyboard-vichan-devel
+
+They will be pulled over time. By the way, copying over those directories
+to a vanilla Tinyboard installation will instantly work.