Fixed auto configuration of the JstlMessageResolver
The JstlMessageResolver was auto-configured because of the presence of the JSTL JAR in the classpath in Thymeleaf apps, only if using the Thymeleaf Tiles2 extra
Improved export feature when using controller
The ExportConf instance built with any controller is now optional. By default, the parameter set via the JSP taglib / Thymeleaf dialect will be used to initialize an ExportConf instance.
ExportConf instance built by hand in a controller will override the default ExportConf built from the request
Cleaned code / added comments
Added missing fileExtension and mimeType attribute of the ExportTag
Added missing "rtexprvalue" in the TLD
Winter cleaning