gitignore: add examples/transcoding

Signed-off-by: Lukasz Marek <lukasz.m.luki2@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

.gitignore

@@ -49,6 +49,7 @@
 /doc/examples/resampling_audio
 /doc/examples/scaling_video
 /doc/examples/transcode_aac
+/doc/examples/transcoding
 /doc/fate.txt
 /doc/print_options
 /lcov/