Use readline for repl

src/main.c

@@ -1,5 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <readline/readline.h>
+#include <readline/history.h>
 
 #include "uclisp.h"
 
@@ -69,13 +71,12 @@ int main(int argc, const char **argv) {
 
     if (argc < 2) {
         while (1) {
-            printf("> ");
-            char *line = NULL;
-            size_t len = 0;
-            ssize_t lineSize = 0;
-            lineSize = getline(&line, &len, stdin);
-            if (lineSize == -1) {
-                return 0;
+            char *line = readline("> ");
+            if (line == NULL) {
+                break;
+            }
+            if (strlen(line) > 0) {
+                add_history(line);
             }
 
             struct ucl_object *sexp = ucl_parse(line);