move-only: Add txorphanage module
Summary:
This module captures orphan tracking code for tx relay.
Can be reviewed with --color-moved=dimmed-zebra
This is a backport of core#21148 [1/14]
https://github.com/bitcoin/bitcoin/pull/21148/commits/9d5313df7eedad8562c822f5477747e924929fd3
Note: I had to change a couple of uint256 type to TxId in a test.
Test Plan: ninja all check-all
Reviewers: #bitcoin_abc, Fabien
Reviewed By: #bitcoin_abc, Fabien
Differential Revision: https://reviews.bitcoinabc.org/D11481