Merge #10484: 0.14 Backports

18476423 [Wallet] unset change position when there is no change on exact match (Gregory Sanders)
ae479bc4 build: fix bitcoin-config.h regeneration after touching build files (Cory Fields)
3d395d68 build: remove wonky auto top-level convenience targets (Cory Fields)
4bc99c3b Add missing <atomic> header in clientmodel.h (Jonas Schnelli)
222f3775 Set both time/height header caches at the same time (Jonas Schnelli)
7da13377 Declare headers height/time cache mutable, re-set the methods const (Jonas Schnelli)
9ac40e85 Update the remaining blocks left in modaloverlay at init. (Jonas Schnelli)
1e936d7e Reduce cs_main locks during modal overlay by adding an atomic cache (Jonas Schnelli)
0aee4a13 Check interruptNet during dnsseed lookups (Matt Corallo)