[mythtv] Transcode first/last frame problem [patch to v0.19]

[David Whyte]

>
> This is the whole point of the patch.  If you use a "delete before"
> marker as the first one then the first frame appears in the output.
> The same as when a "delete after" is the last marker; the last frame
> appears in the output.
>
> If this patch doesn't go in then it means that transcoded videos
> contain one frame of unwanted video at the beginning and the end (if
> using "delete before" as the first marker and "delete after" as the
> last one).
>

Please allow this patch!  I hate those first and last frames that get
left in the transcoded files...even when exporting with Nuvexport!!

Cheers,
Whytey