stats method to report system stats

[Rufus Pollock]

We want to have functions to return total users and total datasets, and users registered in last day.

Acceptance criteria

• total number of users in db, plus number registered in last day - direct access to user db
• total number of datasets (via metastore search API)
• this info can then get added to a tracking spreadsheet - https://docs.google.com/spreadsheets/d/1_rUBr0-nfo2zJdcA5DQ0MNqoWZq0djmokvHDYbu_gQA/edit#gid=0

Tasks:

• create function users_total - get directly from DB
• create function users_last_day - get directly from DB
• create function datasets_total - API call to metastore
• update abovementioned spreadsheet everyday in the morning

[Meiran Zhiyenbayev]

FIXED