BAC-127: import wikicities into devboxes

This script will be executed every week (during weekend probably) to fetch the latest dump of production ``wikicities`` database from S3 into devboxes. It will also add devbox specific rows - for instance ``city_list`` entry for devbox wiki.

Please note that not all tables will be imported (due to its size). The following regexp is used for blacklisting them:

```
"^user_\|wikia_tasks_log\|ach_ranking_snapshots\|city_list_log\|^user$"
```