* Parameters are taken as a hash now - eight or nine function parameters is a whorepile. The parameters are sourced from the new artefactchooser_element api method for blocktypes
 * Because of this, much less data has to be passed through as 'extradata', so removed a bunch of that
 * Removed 'offsetname' configuration, not required anymore.
 * Added a hook to allow blocktypes to affect the sort order for artefacts in the chooser, and a hook to allow them to configure data before it goes to the chosen smarty template for displaying each element in the chooser.