xrootd: implement a xrootd server application

[sbinet]

• [ ] kXR_admin
• [ ] kXR_auth
• [ ] kXR_bind
• [ ] kXR_chmod
• [x] kXR_close
• [ ] kXR_decrypt
• [x] kXR_dirlist
• [ ] kXR_endsess
• [ ] kXR_getfile
• [ ] kXR_locate
• [x] kXR_login
• [ ] kXR_mkdir
• [x] kXR_mv
• [x] kXR_open
• [ ] kXR_ping
• [ ] kXR_prepare
• [x] kXR_protocol
• [ ] kXR_putfile
• [ ] kXR_query
• [x] kXR_read
• [ ] kXR_readv
• [ ] kXR_rm
• [ ] kXR_rmdir
• [ ] kXR_set
• [ ] kXR_sigver
• [x] kXR_stat
• [ ] kXR_statx
• [x] kXR_sync
• [x] kXR_truncate
• [x] kXR_write
• [ ] kXR_verifyw

[EgorMatirov]

• [ ] kXR_admin
• [ ] kXR_auth
• [ ] kXR_bind
• [ ] kXR_chmod
• [x] kXR_close
• [ ] kXR_decrypt
• [x] kXR_dirlist
• [ ] kXR_endsess
• [ ] kXR_getfile
• [ ] kXR_locate
• [x] kXR_login
• [ ] kXR_mkdir
• [x] kXR_mv
• [x] kXR_open
• [ ] kXR_ping
• [ ] kXR_prepare
• [x] kXR_protocol
• [ ] kXR_putfile
• [ ] kXR_query
• [x] kXR_read
• [ ] kXR_readv
• [ ] kXR_rm
• [ ] kXR_rmdir
• [ ] kXR_set
• [ ] kXR_sigver
• [x] kXR_stat
• [ ] kXR_statx
• [x] kXR_sync
• [x] kXR_truncate
• [x] kXR_write
• [ ] kXR_verifyw

[sbinet]

copied your bullet-list in the original issue message.