Add more KPIs

We may want to extend our collection of key performance indicators that we provide (& collect in the HIFIS cloud service repo).

Possible extensions are:

• number of organizations of the users
• number of pids (for the b2inst usage)
• number of uploaded attachments (for the s3 storage usage)
• number of datastream links (for the TSM interface)
• number of currently used (mounted) devices? (ala there are so many devices in use right now - all registered within the sms)