Fix/log paginate

[rickimoore]

It is possible to have high amount of ERRO and CRIT logs while nodes are running. This can cause Siren to store a large amount of logs and slow down the api request, subsequently making the ssr first build slower when navigating to the main dashboard.

This pr resolves that buy creating a pagination effect for the priority logs displayed in the alerts component. By default Siren will fetch the most recent 15 logs and will allow the user to request via button. this prevents the first request from dumping 100s of logs and slowing down siren

https://github.com/sigp/siren/issues/251