added translator credits to i18n documentation

docs/i18n.md

@@ -32,3 +32,20 @@ If the upstream changes, do a `git pull` and then repeat from step 2.
 Before opening a pull request, please run `./tools/po-update.sh` again. It will
 format and sort the translation file, and ensure a minimal diff when updating
 a translation.
+
+
+# Supported languages
+
+Currently Solaar has been translated in the following languages:
+
+- Français: [Papoteur][papoteur], [David Geiger][david-geiger],
+  [Damien Lallement][damsweb]
+- Polski: [Adrian Piotrowicz][nexces]
+- Română: Daniel Pavel
+- Svensk: [Daniel Zippert][zipperten], Emelie Snecker
+
+[papoteur]: http://github.com/papoteur
+[david-geiger]: http://github.com/david-geiger
+[damsweb]: http://github.com/damsweb
+[nexces]: http://github.com/nexces
+[zipperten]: http://github.com/zipperten