update lab1-8 codes and docs. now version is 0.2

code/lab8/kern/fs/fs.c

@@ -78,7 +78,7 @@ files_closeall(struct files_struct *filesp) {
 }
 
 int
-dup_fs(struct files_struct *to, struct files_struct *from) {
+dup_files(struct files_struct *to, struct files_struct *from) {
 //    cprintf("[dup_fs]\n");
     assert(to != NULL && from != NULL);
     assert(files_count(to) == 0 && files_count(from) > 0);