Add statistics to the admin

[vohmar]

We need to add statistical data to the admin interface Implement the same statistics that are presented on the internet.ee web page: https://www.internet.ee/abi-ja-info/statistika in admin present the stats in numbers/tables

Core data:

• domain count current
• domain count change in previous month and same month a year before - count + percentage
• domain renewal rate during the previous 12 months
• paid operations (new registration + renewals) count in previous month and same month a year before - count + percentage
• new registrations in previous month and same month a year before - count + percentage
• renewals in previous month and same month a year before - count + percentage
• deletions in previous month and same month a year before - count + percentage

additionally we could collect monthly data in the table and plot the chart to spot the trends

as an added bonus would be having a market share info - we could get that from CENTR stats

[vohmar]

Registrar coordinator wants stats about registrar market share: domain count per registrar at the end of previous year; market share percentage at the end of previous year; domain count per registrar at the end of previous month; market share percentage at the end of previous month; domain count change (at the end of precious month - at the end of previous year); market share change (at the end of precious month - at the end of previous year)