ajout des builtins pwd cd et export

srcs/builtins/pwd.c

@@ -0,0 +1,15 @@
+
+#include "minishell.h"
+
+int	builtin_pwd(int argc, char *argv[], t_all *c)
+{
+	char	*pwd;
+
+	(void)argc;
+	(void)argv;
+	(void)c;
+	pwd = getcwd(NULL, 0);
+	write(1, pwd, ft_strlen(pwd));
+	write(1, "\n", 1);
+	return (0);
+}