Add support for Broken Sword 1 German CD version and English GOG version

Summary

This merge request adds support for the following versions of Broken Sword 1:

• German CD version.
• English GOG.com version.

Package structure

• Video packages are still modelled as expansions as they are language-specific and not available for every version.
• Music packages are modelled as common dependencies as they are not language-specific and each game version should provide some kind of music.

I've also tried to modell the music packages as expansions like follows:

  brokensword1-ogg-music:
    longname: 'Broken Sword 1 - music compressed with Ogg Vorbis'
    expansion_for: brokensword1-data

But apparently, this relation doesn't seem to work for virtual packages like brokensword1-data as it seems to require a concrete (and thereby language-specific) package like the following warning suggests:

$ game-data-packager \
    --package brokensword1-ogg-music \
    --package brokensword1-en-data \
    --package brokensword1-en-dxa-video \
    brokensword1 /path/to/gog_broken_sword_the_shadow_of_the_templars_2.0.0.4.sh
[...]
WARNING:game_data_packager.build:won't generate 'brokensword1-ogg-music' expansion,
    because full game "brokensword1-data" is neither available nor already installed;
    and we are packaging "brokensword1-en-data" instead.
[...]

Known issues

• Package brokensword1-orig-music produces unnecessary desktop file /usr/share/applications/brokensword1-orig-music.desktop.
• Package brokensword1-ogg-music produces unnecessary desktop file /usr/share/applications/brokensword1-ogg-music.desktop.
• Package brokensword1-flac-music probably also produces an unnecessary desktop file but I can't test this case as I do not have the required flac files.