Add m_avoid_address_reuse flag to coin control object.
Add avoid_reuse wallet flag and accompanying strings/caveats.
https://github.com/bitcoin/bitcoin/pull/13756/commits/eec15662fad917b169f5e3b8baaf4301dcf00a7b
---
Depends on D6369
Partial backport of Core [[https://github.com/bitcoin/bitcoin/pull/13756 | PR13756]]