Add initial support for bucket lifecycle (#7563)

This PR is based off @sinhaashish's PR for object lifecycle
management, which includes support only for,
- Expiration of object
- Filter using object prefix (_not_ object tags)

N B the code for actual expiration of objects will be included in a
subsequent PR.

cmd/generic-handlers.go

@@ -473,7 +473,6 @@ var notimplementedBucketResourceNames = map[string]bool{
 	"acl":            true,
 	"cors":           true,
 	"inventory":      true,
-	"lifecycle":      true,
 	"logging":        true,
 	"metrics":        true,
 	"replication":    true,