Add CWS listing description

In order to be able to translate the CWS listing description to other
languages in Pontoon, we must add it to the Git repo. This CL does that
and adds the configuration so Pontoon manages translations of that file.

Bug: twpowertools:40
Change-Id: I4c0a6341ae1c44dcb5d8c744b708a24b05c2857e
diff --git a/i18n-config.toml b/i18n-config.toml
index 10a1b23..8c02374 100644
--- a/i18n-config.toml
+++ b/i18n-config.toml
@@ -15,3 +15,7 @@
   reference = "src/static/_locales/en/messages.json"
   l10n = "src/static/_locales/{android_locale}/messages.json"
+  reference = "cws/en/listing-description.lang"
+  l10n = "cws/{android_locale}/listing-description.lang"