Function dt_node_int

* The original rules for integer constant typing are described in K&R[A2.5.1]. * However, since we support long long, we instead use the rules from ISO C99 * clause 6.4.4.1 since that is where long longs are formally described. The * rules require us to know whether the constant was specified in decimal or * in octal or hex, which we do by looking at our lexer's 'yyintdecimal' flag. * The ty