The genesis block is skipped when indexing

[Jannis]

Do you want to request a feature or report a bug?

Bug

What is the current behavior?

All subgraphs start indexing from block genesis + 1, skipping the genesis block.

What is the expected behavior?

All subgraphs start indexing from genesis, rather than genesis + 1.

[Jannis]

This can be fixed by making the latest block pointer on a subgraph optional and starting with genesis if it is None. I already have this working locally, just need to pull it out into a PR.

[Jannis]

Resolved via #1297.