Add comments

main.c

+/*
+ * Authors: Krasimir Balchev, Stefan Costica, Nikolay Tsanov, Mihail Hristov, Enrique Martín Ocaña
+ * Group Number: 18
+ * Purpose: A simple shell implemented in C, it supports the built-in UNIX commands, history invocations, aliases (recursive aliases are possible).
+ * Language: C
+ */
+
 #include <stdio.h>
 #include <string.h>
 #include "shell.h"
 
+// Start the shell
 int main( void ) {
-    // Load files
-    // load_history();
-
     //Run shell
     run_shell();