091a9ae remove minimum total fee option (Gregory Sanders)

Tree-SHA512: 9be4df3dab0219f30917211408f47b242f7c96dd7663b06ab1cf3cc63027f14956dc680883be6c58673b6452d0f339cf893694e4f21d0d248e70760614d5a344

…erate

184f878 wallet_bumpfee.py: add test for change key preservation (Gregory Sanders)
d08becf add functional tests for feerate bumpfee with adding inputs (Gregory Sanders)
0ea47ba generalize bumpfee to add inputs when needed (Gregory Sanders)

Pull request description:

  When targeting a feerate using `bumpfee`, call a new function that directly uses `CWallet::CreateTransaction` and coin control to get the desired result. This allows us to get a superset of previous behavior, with an arbitrary RBF bump of a transaction provided it passes the preconditional checks and spare confirmed utxos are available.

  Note(s):
  0) The coin selection will use knapsack solver for the residual selection.
  1) This functionality, just like knapsack coin selection in general, will hoover up negative-value inputs when given the chance.
  2) Newly added inputs must be confirmed due to current Core policy. See error: `replacement-adds-unconfirmed`
  3) Supporting this with `totalFee` is difficult since the "minimum total fee" option in `CreateTransaction` logic was (rightly)taken out in #10390 .

ACKs for commit 184f87:
  jnewbery:
    utACK 184f878

Tree-SHA512: fb6542bdfb2c6010e328ec475cf9dcbff4eb2b1a1b27f78010214534908987a5635797196fa05edddffcbcf2987335872dc644a99261886d5cbb34a8f262ad3e

091a9ae remove minimum total fee option (Gregory Sanders)

Tree-SHA512: 9be4df3dab0219f30917211408f47b242f7c96dd7663b06ab1cf3cc63027f14956dc680883be6c58673b6452d0f339cf893694e4f21d0d248e70760614d5a344