Copy patches from SLE12 into Factory:

- Add "vsftpd-die-with-session.patch" to fix a bug in vsftpd that
would cause SSL protocol errors, aborting the connection, whenever
system errors occurred that were supposed to be non-fatal.
[bsc#1044292]

- Add "vsftpd-mdtm-in-utc.patch" to fix interoperability issue with
various ftp clients that arose when vsftpd is configured with
option "use_localtime=YES". Basically, it's fine to use local time
stamps in directory listings, but responding to MDTM commands with
any time zone other than UTC directly violates RFC3659 and leads
FTP clients to misinterpret the file's time stamp. [bsc#1024961]

- Add "vsftpd-append-seek-pipe.patch" to allow the FTP server to
append to a file system pipe. [bsc#1048427]