Optimize database structure

[Eternali]

Right now the database is still geared towards a "transactions first" UI. Since we now show blocks primarily, it would be good to cache block info and do a bit of restructuring in the database.

[Eternali]

The goal is to have an intermediate layer in which every rpc request to the node is cached in the database. This way the actual connected node will not be bombarded by requests under heavy traffic. Instead all requests will be delegated to a cloud database which can be much more easily scaled to handle high volumes of traffic.