upsertAccount in base.eth Registrar handler

[lightwalker-eth]

Issue link: #24 (comment)

@shrugs Appreciate your advice here. We've already put a big effort into PR 24 and so creating this issue so we can merge PR 24 and follow up on this separately.

[shrugs]

correct.

technically: ponder doesn't enforce foreign key constraints in the postgres schema, so technically either order works but we should prefer the order you've suggested here, since domain records should depend on account record existing.

the "insert account, create domain" is a primary pattern of the subgraph, and i don't think its use here needs to be particularly documented.

#24 (comment)