Add change user password from CLI documentation

support/doc/tools.md

@@ -18,6 +18,7 @@
   - [prune-storage.js](#prune-storagejs)
   - [optimize-old-videos.js](#optimize-old-videosjs)
   - [update-host.js](#update-hostjs)
+  - [reset-password.js](#reset-passwordjs)
   - [REPL (Read Eval Print Loop)](#repl-read-eval-print-loop)
     - [.help](#help)
     - [Lodash example](#lodash-example)
@@ -227,6 +228,14 @@ to run:
 $ sudo -u peertube NODE_CONFIG_DIR=/var/www/peertube/config NODE_ENV=production npm run update-host
 ```
 
+### reset-password.js
+
+To reset a user password from CLI, run:
+
+```
+$ sudo -u peertube NODE_CONFIG_DIR=/var/www/peertube/config NODE_ENV=production npm run reset-password -- -u target_username
+```
+
 ### REPL ([Read Eval Print Loop](https://nodejs.org/docs/latest-v8.x/api/repl.html))
 
 If you want to interact with the application libraries and objects even when PeerTube is not running, there is a REPL for that.