Allows per output xml and cc files

[g-maxime]

Fixes #811

Snapshot: https://mediaarea.net/download/snapshots/binary/dvrescue/20240730-2/

Caption part is untested.

Sample command:
./dvrescue device://0 --merge-ignore-concealed --merge-ignore-speed -c ignore.scc -x ignore.xml -m ignore.dv --merge-output-concealed --merge-output-speed -c output.scc -x output.xml -m output.dv

[dericed]

I tested with these commands, during tape playback I forced the deck to rewind, ff, and rewind to create non-playback-speed frames.

dvrescue device://0 -y --merge-ignore-concealed --merge-ignore-speed -c ignore.scc -x ignore.xml -m ignore.dv --merge-output-concealed --merge-output-speed -c output.scc -x output.xml -m output.dv

I also wanted to verify that xml during capture and after capture is the same as they should match since the xml depict the output rather than input, so I made these with

dvrescue output.dv -x output.dvrescue.analyzed-after-capture.xml
dvrescue ignore.dv -x ignore.dvrescue.analyzed-after-capture.xml

The output.xml matches, mostly, except, the size attribute depicts the input rather than output:

diff output.dvrescue.analyzed-after-capture.xml output.xml 
8c8
< 	<media ref="output.dv" format="DV" size="51360000">
---
> 	<media ref="output.dv" fromCapture="device://0" format="DV" size="51359744">

ls -l output.dv
-rw-r--r--@ 1 drice  staff  51360000 Jan  7 12:32 output.dv

The ignore*.xml files are very different. Also ignore.dv contains many frames that should have been ignored (both speed and concealed), though many frames are ignored. All files are at https://archive.org/download/output_20250107.