Added instructions for migrate

README.md

@@ -17,6 +17,8 @@
 * Copy ```config.json``` and modify it (setup ZNC etc.)
   - ```cp config.json-example config.json```
   - ```vim config.json```
+* If database is empty, run the migrate script to populate the database with old nxy data:
+  - ```python bot/migrate.py```
 * Leave (auto) activated virtualenv and exit the bot's shell
   - ```deactivate && exit```
 * Copy systemd unit and enable it (would recommend the ```/usr/local``` prefix). Don't forget to modify the systemd unit if your user and home directory are different!