Factory contract indexing

[joshstevens19]

Some contracts deploy contracts inside themselves and, in turn, then emit the new address for the indexing to listen out for. For example, Uniswap Pools is a good example, we should allow rindexer to support factory style track, a bit of work has already been done on this in the YAML itself it just needs the code to track it and index the new addresses as they are emitted.