fixes internal scripts of apachewebserver plugin
adds method to get all relationshiptemplate to templateplancontext
fixes bug were empty properties (e.g. <prop></prop>) wouldn't be initialized in build plan
removes unnecessary constructor in ubuntuvm plugin class
adds feature to plugins (invoker, apachewebserver, mysqldatabase, mysqlserver, phpapp, phpappconnectstomysqldv, ubuntuvm, php) which allows to model cloud credentials into topology template and use given values inside plan