The STCN script now copes with all Picarta scraping tasks!

* [STCN_GENERAL,NEW] Added wrapper ppn//0.
* [STCN_SCRAPE,NEW] Rewrote the scraping of additional Picarta data.
* [STCN_SCRIPT,EXT] Changes to the STCN script based on improvements to SCRIPT_EXT (in PGC).
* [STCN_SCRIPT,SC] Simplified script by leaving out the to-file checks (now automated).
* [STCN_SCRIPT,EXT] Added a script stage for copying the Picarta topics and for adding these topics to the Picarta scrape.