Add block number and log index in state sync object and make stateId uint

[jdkanani]

Add/change the following properties in the state sync object for easier query:

1. Add block number
2. Add log index for that particular state sync (not sure if this is provided by graph protocol for a particular event)
3. Make state id uint (instead of string) for the easier query. I am not sure if the query is possible without making uint.