binkcadm.bat create users -r master -f add-user.json

{
    "username" : "myUserName",
    "enabled" : true,
    "credentials" : [ {
        "type" : "password",
        "hashedSaltedValue" : "encoded password string",
        "salt" : "salt string",
        "hashIterations" : 27500,
        "algorithm" : "pbkdf2-sha256"
     } ],
    "realmRoles" : [ "admin" ]
}