ANTLR error handling Edit

Created 6/17/2007, updated 5/18/2017

C target error handling

See also

Example of custom error handling (Java target): http://www.antlr.org/wiki/display/ANTLR3/6.+Advanced+processing
antlr-interest thread, "Wondering about: Error handling": http://www.antlr.org:8080/pipermail/antlr-interest/2007-June/021448.html