SCUMM: Add support for Steam versions of Indy 3, Indy 4, Loom and Dig

Many Thanks to Ben Castricum for the original patch
SCUMM: Add support for CD audio tracks in the Steam versions of Loom

Many Thanks to Ben Castricum for the original patch
Merge pull request #470 from bluegr/Lucasarts_Steam

SCUMM: Add support for Steam versions of Indy 3, Indy 4, Loom and Dig
SCUMM: Remove empty line before license header.
SCUMM: Use spaces instead of tabs in comments.
SCUMM: Remove unused variable.
SCUMM: Slight formatting fixes.
SCUMM: Fix a subtle bug in Sound::getCDStatus() for Loom Steam
SCUMM: Simplify index file handling for Steam versions.

This also makes sure that all extra needed detection data for the Steam
releases is located inside detection.cpp.
SCUMM: Cleanup.
I18N: Update French translation
SWORD1: Tweak MPEG-2 cutscenes error message

Beside making the message slightly better imho, it is also now
identical to the same message in BS2 and also more coherent with
the DXA message.
Updated 1.7.0 release date in German NEWS (Neues).
Merge pull request #477 from SimSaw/master

NEWS: Updated 1.7.0 release date in German NEWS (Neues).
I18N: Update Italian translation (from patch #1608)
NEVERHOOD: Play a single sound when losing the memory puzzle (bug #6672)

When the memory puzzle is reset, each revealed tile gets hidden again.
When a lot of tiles were hidden, the multiple clicking sounds would
fill the available sound slots. To avoid this, only a single click is
sounded when losing
I18N: Update Spanish translation from patch #1609
NEWS: Mention support for the Lucasarts Steam versions
NEWS: Typo.
MT32: Copyright year bump