wenzelm [Mon, 28 Dec 2009 18:40:13 +0100] rev 34198
moved Library.decode_permissive_utf8 to Isabelle_System;
moved Library.with_tmp_file to Isabelle_System;
added Isabelle_System.read_file/write_file;
added Isabelle_System.system_out, with propagation of thread interrupts and process shutdown (global CTRL-C);