Add priority bump to coins moving to chain, too.
Add priority bump to coins moving to chain, too.

This addresses bottlenecks where locked coins are in a few outputs
with lots of contention

jtimon/elements,jtimon/elements,NunoEdgarGub1/elements,jtimon/elements,truthcoin/blocksize-market,truthcoin/blocksize-market,apoelstra/elements,NunoEdgarGub1/elements,jtimon/elements,gwillen/elements,NunoEdgarGub1/elements,pstratem/elements,apoelstra/elements,droark/elements,truthcoin/blocksize-market,sipa/elements,fussl/elements,aburan28/elements,pstratem/elements,aburan28/elements,droark/elements,droark/elements,droark/elements,droark/elements,truthcoin/blocksize-market,gwillen/elements,apoelstra/elements,NunoEdgarGub1/elements,jtimon/elements,apoelstra/elements,aburan28/elements,fussl/elements,sipa/elements,pstratem/elements,NunoEdgarGub1/elements,apoelstra/elements,truthcoin/blocksize-market,aburan28/elements,truthcoin/blocksize-market,fussl/elements,sipa/elements,fussl/elements,gwillen/elements,aburan28/elements,aburan28/elements,gwillen/elements,gwillen/elements,jtimon/elements,sipa/elements,pstratem/elements,droark/elements,sipa/elements,NunoEdgarGub1/elements,pstratem/elements,pstratem/elements,fussl/elements,apoelstra/elements,gwillen/elements,fussl/elements,sipa/elements