implement more batch jobs

[gotchazipc]

We need several batch jobs keep system clean

1. remove inactive accounts automatically #90 - remove inactive accounts
2. apps/deleted directory should be garbage-collected  #89 - remove apps/deleted (daily or weekly)
3. remove expired tokens in DB (in mem_token)
4. remove temp keys (in mem_temp_key table) unused
5. garbage cleaning fs_wfs_del (just remove all)

• each job should be a batch module in batch unit.
• we may have to fix or create APIs.