Improve Option documentation and add MaybeSome function #16160

Job	Run time
RPC and mobile compilation check	1m 49s
Sqlc check	2m 49s
check commits	6m 9s
cross compilation	32m 20s
lint code	3m 55s
sample configuration check	4m 8s
run unit tests (btcd unit-cover)	9m 30s
check pinned dependencies (google.golang.org/grpc v1.59.0)	4s
run unit tests (unit tags="kvdb_etcd")	19m 44s
run ubuntu itests (btcd, backend=btcd cover=1)	28m 26s
check pinned dependencies (github.com/golang/protobuf v1.5.3)	5s
run unit tests (unit tags="kvdb_postgres")	18m 33s
run ubuntu itests (bitcoind, backend=bitcoind cover=1)	37m 31s
run unit tests (unit tags="kvdb_sqlite")	17m 26s
run ubuntu itests (bitcoind-notxindex, backend="bitcoind notxindex")	36m 39s
run unit tests (btcd unit-race)	36m 43s
run windows itest	5m 14s
run ubuntu itests (bitcoind-rpcpolling, backend="bitcoind rpcpolling" cover=1)	38m 31s
run unit tests (unit-module)	1m 4s
run ubuntu itests (bitcoind-etcd, backend=bitcoind dbbackend=etcd)	52m 58s
run ubuntu itests (bitcoind-postgres, backend=bitcoind dbbackend=postgres)	1h 10m 17s
run macOS itest	51m 44s
run ubuntu itests (bitcoind-sqlite, backend=bitcoind dbbackend=sqlite)	39m 10s
check release notes updated	5s
run ubuntu itests (bitcoind-postgres-nativesql, backend=bitcoind dbbackend=postgres nativesql=true)	1h 10m 53s
run ubuntu itests (bitcoind-sqlite-nativesql, backend=bitcoind dbbackend=sqlite nativesql=true)	39m 41s
run ubuntu itests (neutrino, backend=neutrino cover=1)	35m 14s
finish	3s
	11h 0m 45s

Provide feedback