rewrite using the editline library.

tiny line editing, dunno why we're not using readline, probably because
of some licensing stuff.

c/mul/Makefile

@@ -4,7 +4,7 @@ run: mul
	./mul
mul: main.c
	$(CC) main.c -o mul
	$(CC) -ledit main.c -o mul
clean:
	rm -f mul

c/mul/main.c

@@ -1,14 +1,17 @@
#include <stdio.h>
#include <editline/readline.h>
int main(int argc, char** argv) {
	puts("mul v0.0.1\n");
	while (1) {
		fputs("> ", stdout);
		fgets(input, 2048, stdin);
		char* input = readline("> ");
		add_history(input);
		printf("%s, yes.", input);
		free(input);
	}
	return 0;