added action to make antiquoted cartouche;

back to scala-2.12.2, after a41435469559;

back to scala-2.11.8 due to apparent non-termination of HOL-Codegenerator_Test;

updated to scala-2.12.2;

tuned signature;

more formal treatment of control symbols;

added isabelle update_cartouches option -t;

another antiquotation short form: undecorated cartouche as alias for @{text};
document antiquotation @{text} ignores option "source";

tuned;

support control symbol antiquotations;

proper headers;

support ML antiquotations in Scala;
tuned -- more uniform ML vs. Scala;

antiquotations within plain text: Scala version in accordance to ML;