e6756ad Switch CCoinsMap from boost to std unordered_map (Pieter Wuille)
344a2c4 Add support for std::unordered_{map,set} to memusage.h (Pieter Wuille)
Tree-SHA512: 51288301e7c0f29ffac8c59f4cc73ddc36b7abeb764009da6543f2eaeeb9f89bd47dde48131a7e0aefad8f7cb0b74b2f33b8be052c8e8a718339c3e6bb963447
Associate with each CTxMemPoolEntry all the size/fees of descendant
mempool transactions. Sort mempool by max(feerate of entry, feerate
of descendants). Update statistics on-the-fly as transactions enter
or leave the mempool.
Also add ancestor and descendant limiting, so that transactions can
be rejected if the number or size of unconfirmed ancestors exceeds
a target, or if adding a transaction would cause some other mempool
entry to have too many (or too large) a set of unconfirmed in-
mempool descendants.