14916: Update for pre1

14888: modify build files for COPYING.LIB->LGPL2.1.txt, as per http:/…

…/article.gmane.org/gmane.comp.graphics.inkscape.devel/48212

13516: update translations

13429: LPEItem enabling/disabling: rewrite mechanism to be more robus…

…t. the previous nesting behavior was not used, and code relied on non-nesting behavior.

13341: Documentation. Advanced tutorial update (not fully translated).