Please support 'configs' replace 'params' in --data-binary

[deanrobin]

I use this project very long time.
But ,today, my client need 'configs' in data-binary, not support 'params', please update it.

[anysoft]

https://github.com/briandilley/jsonrpc4j/blob/master/src/test/java/com/googlecode/jsonrpc4j/client/JsonRpcClientTest.java
final String auth = "auth";
final String authValue = "secret";
client.setAdditionalJsonContent(new HashMap<String, Object>() {
{
put(auth, authValue);
}
});
client.invoke("test", new Object[]{1, 2}, byteArrayOutputStream);

[anysoft]

maybe you need to fork this repo and modify it yourself.