Log Message:
Update k3b to 0.12.15

* Write more metadata tags in the default setup of the external encoder
  plugin.
* Fixed on-the-fly Video DVD creation.
* Fixed data project verification in case filenames had to be shortened
  due to Joliet limitations.
* Use -dvd-compat parameter to close DVDs in on-the-fly mode.
* Fixed libdvdcss handling (again), no crashes anymore.
* Fixed the "invalid url" bug.
* Use SG IO for scsi commands with newer linux kernels. This should fix
  problems with scsi device detection.
* Warn about shortened filenames due to Joliet restrictions before
  starting the burning process.