This release in not backward compatible - custom ejs templates as well as koa+express requires minimal manual adjustments!

• Added: template support for pagetitle (automatically set if not defined)
• Added: option to set the pagetitle directly via payload.pagetitle (koa+expressjs)
• Added: filter function to dynamically manipulate the errordata object (koa+expressjs)
• Added: support for additional variables/payloads
• Added: support for placeholders to static page generator
• Added: iso-639-1 language attribute (derived from page lang)
• Added: error/exception object available via error (koa+expressjs)
• Added: onError callback as debug error handler (not to be used in production)
• Changed: moved footer content into payload object
• Changed: all variables within the ejs template are only accessible via vars object