archaius-core/src/main/java/com/netflix/config/ConcurrentCompositeConfiguration.java
@Override
    public void addProperty(String key, Object value) {
        containerConfiguration.addProperty(key, value);
    }
@Override
    public void addProperty(String key, Object value) {
        containerConfiguration.addProperty(key, value);
    }
Add the property with the <em>container configuration</em>.
<b>Warning: </b>{@link #getProperty(String)} on this key may not return the same value set by this method
if there is any other configuration that contain the same property and is in front of the
<em>container configuration</em> in the configurations list.