====== Merge MKV Files ======

<file>
sudo apt-get install mkvtoolnix

mkvmerge -o out.mkv title1.mkv +title2.mkv +title4.mkv +title5.mkv +title7.mkv +title8.mkv +title9.mkv +title10.mkv
</file>
  * It seems like it is important to add "+" to every input file after the first file

====== Convert MKV to MP4 ======
<file>
avconv -i input.mkv -codec copy output.mp4
</file>