#579 Missing dvd-cache temp directory causes transcoding to fail

[Paul Kohout]

If the %TEMP%\dvd-cache directory is missing (at least in Windows), the ffmpeg command to transcode fails. See output below (portions redacted).

DVDStyler v2.9 beta 2
Windows 7 (build 7601, Service Pack 1), 64-bit edition
FFmpeg: libavformat 56.15.102, libavcodec 56.14.100, libavutil 54.15.100
...
Transcode/remultiplex
Add file to cache:C:\Users\XXX\AppData\Local\Temp\dvd-cache\entry001.vob
Transcode video file: XXX.AVI
Need encode: true, use mplex: false
Executing command: ffmpeg -threads 8 -i "XXX.AVI" -f dvd -c:v:0 mpeg2video -aspect 16:9 -s 720x480 -r 24000/1001 -g 18 -b:v:0 8000000 -maxrate:v:0 8000000 -minrate:v:0 8000000 -bufsize:v:0 1835008 -packetsize 2048 -muxrate 10080000 -vf scale=540:480,pad=720:480:90:0 -b:a 192000 -ar 48000 -c:a:0 ac3 -map 0:v -map 0:a -map -0:s "C:\Users\XXX\AppData\Local\Temp\dvd-cache\entry001.vob"
ffmpeg version N-68211-g4a0b1d9 Copyright (c) 2000-2014 the FFmpeg developers
  built on Dec  4 2014 22:07:45 with gcc 4.9.2 (GCC)
  libavutil      54. 15.100 / 54. 15.100
  libavcodec     56. 14.100 / 56. 14.100
  libavformat    56. 15.102 / 56. 15.102
  libavdevice    56.  3.100 / 56.  3.100
  libavfilter     5.  2.103 /  5.  2.103
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Guessed Channel Layout for  Input Stream #0.1 : mono
Input #0, avi, from 'XXX.AVI':
  Duration: 00:00:16.06, start: 0.000000, bitrate: 3007 kb/s
    Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj420p(pc, bt470bg/unknown/unknown), 320x240, 2649 kb/s, 24.41 fps, 24.41 tbr, 24.41 tbn, 24.41 tbc
    Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 22050 Hz, 1 channels, s16, 352 kb/s
C:\Users\XXX\AppData\Local\Temp\dvd-cache\entry001.vob: No such file or directory