Update to support rename flags in #652 breaks V3 SFTP Protocol and causes errors with AWS SFTP Server

[SteveReedMO]

The pull request for #652 enables the ability to set rename flags. This was recently rolled into V0.32.0.

I believe this is a SFTP V5+ only feature it should not be enabled for SFTP V3/4 servers that will not support this.

As sshj has a max SFTP version of 3. It's rename packets should have the following structure

byte SSH_FXP_RENAME
uint32 id
string oldpath
string newpath

and not this structure, which is what V0.32.0 is currently sending for any rename

byte SSH_FXP_RENAME
uint32 id
string oldpath
string newpath
uint32 flags

Servers not expecting the extra uint32 flag at the end of the packet may experience issues.

We have witnessed the change in behaviour from V0.31.0 to V0.32.0 using this library with the AWS Transfer Family SFTP Server.

On a file rename we now see the following stacktrace

net.schmizz.sshj.sftp.SFTPException: Timeout expired
at net.schmizz.sshj.sftp.SFTPException$1.chain(SFTPException.java:33)
at net.schmizz.sshj.sftp.SFTPException$1.chain(SFTPException.java:26)
at net.schmizz.concurrent.Promise.retrieve(Promise.java:139)
net.schmizz.sshj.sftp.SFTPEngine.doRequest(SFTPEngine.java:144)
net.schmizz.sshj.sftp.SFTPEngine.doRequest(SFTPEngine.java:144)
net.schmizz.sshj.sftp.SFTPEngine.remove(SFTPEngine.java:211)
net.schmizz.sshj.sftp.SFTPClient.rm(SFTPClient.java:129)

and this error

ERROR [Timer-Driven Process Thread-10] net.schmizz.concurrent.Promise <<sftp / 13>> woke to: net.schmizz.sshj.sftp.SFTPException: EOF while reading packet