add comment regarding tar error

README.md

@@ -555,6 +555,10 @@ This is the same issue as with Samba. `rename` returns `EXDEV` (in our case that
 
 To create a `$topdir/.Trash` directory as defined in the standard use the [mergerfs-tools](https://github.com/trapexit/mergerfs-tools) tool `mergerfs.mktrash`.
 
+#### tar: Directory renamed before its status could be extracted
+
+Make sure to use the `use_ino` option.
+
 #### Supplemental user groups
 
 Due to the overhead of [getgroups/setgroups](http://linux.die.net/man/2/setgroups) mergerfs utilizes a cache. This cache is opportunistic and per thread. Each thread will query the supplemental groups for a user when that particular thread needs to change credentials and will keep that data for the lifetime of the thread. This means that if a user is added to a group it may not be picked up without the restart of mergerfs. However, since the high level FUSE API's (at least the standard version) thread pool dynamically grows and shrinks it's possible that over time a thread will be killed and later a new thread with no cache will start and query the new data.

man/mergerfs.1

@@ -1197,6 +1197,9 @@ which many probably do.
 To create a \f[C]$topdir/.Trash\f[] directory as defined in the standard
 use the mergerfs\-tools (https://github.com/trapexit/mergerfs-tools)
 tool \f[C]mergerfs.mktrash\f[].
+.SS tar: Directory renamed before its status could be extracted
+.PP
+Make sure to use the \f[C]use_ino\f[] option.
 .SS Supplemental user groups
 .PP
 Due to the overhead of