Modify API to handle also ERC20 tokens.
Modify community_tokens table - keep supply as string since string is easly convertible to bigint.BigInt.
Use bigint.BigInt for supply functions and fields.
Issue #11129
This is the first step of improvements over keypairs/keycards/accounts.
- `SyncKeypairFull` protobuf removed
- `SyncKeypair` protobuf is used for syncing all but the watch only accounts
- `SyncAccount` is used only for syncing watch only accounts
- related keycards are synced together with a keypair
- on any keypair change (either it's just a keypair name or any change made over an
account which belongs to that keypair) entire keypair is synced including related keycards
- on any watch only account related change, that account is synced with all its details