- Sticky Actions: mentawai simple and efficient support for continuations

- formSkin tag (Dyntag): build the form structure based on a pre-defined skin with one tag

- better implementation for outError, outErrors, outMessage, outMessages, outFieldErrors based on ConditionalTag base class. (No need for isNull anymore!)

- org.mentawai.core.Configurable interface, so now you can also configure the action inside its class