Implement default max-block-count value

[kauri-hero]

Most of the feedback from the RPC providers has indicated that not having a smaller max block count will be a regular timeout issue as the range of scans increases. This will occur if the user is offline for more that a few days.

Implement max_block_count value of 100,000 as default value.

if the RPC response provides another value, then the logic will handle adjusting for that anyways.

GH-606 has made good improvements with this aspect, allowing startBlock for new database to be brought in from head of chain.

This card will further reduce scanning issues in future for serving Nodes