…tructs, splits them into pre/post NU6 funding streams, and adds them as a field on `testnet::Parameters`

…onversion logic with constraints.

Minor refactors

…red Testnets, but that being okay since configured testnet parameters are checked when they're being built

…ixes test logic

…nd TODOs

…ams, updates the `miner_fees_are_valid()` and `subsidy_is_valid()` functions to check that the deferred pool contribution is valid and that there are no unclaimed block subsidies after NU6 activation, and adds some TODOs

…too, adds Mainnet/Testnet NU6 activation heights, fixes lints/compilation issue

…est_funding_stream_values()` to use a configured testnet with the post-NU6 Mainnet funding streams height range

… as a block submission

…6 height ranges to constants, updates TODO

…tream from `fundingstreams` field

…s instead of an option of an iterator, updates a comment quoting the coinbase transaction balance consensus rule to note that the current code is inconsistent with the protocol spec, adds a TODO for updating the quote there once the protocol spec has been updated.