Add multistream stats

[artandor]

Is your feature request related to a problem? Please describe.
Having to go to all platform's dashboard is painfull and we have no clear visibility over our stats on ALL platforms.

Potential Stats to track

• Average viewers multiplatform stats tracking #72
• Add followers to multi platform stats tracking #74
• Paid subscribers multiplatform stats tracking #73

We should display this data on a dedicated "stat" page.

• Create a dedicated stat page that displays the tracked multistat charts #75

Describe the solution you'd like
A dashboard that shows stats of all platforms, what comes from where, ... would be beneficial imo.

Additional context