SCI: Fix bug #3605269 - "SCI: KQ5 Windows CD - Game Hangs Before Final Battle"

This is caused because songs 1840, 1843 and 1849 are all missing their special
SCI signaling channel (channel 15), so the game scripts wait indefinitely for
signals which are never set
SCI: Set the song's sound queue signal to -1 when stopping a sound, like SSCI does

Previously, we set the signal of the sound objects themselves to -1, but set the
sound queue's signal to 0. This now matches the original behavior.
HOPKINS: Some renaming in TalkManager
SCUMM: More fixes in INSANE
SCUMM: Fix bug #3575444: "FT: Enemy behaviour in biker fight"

Also fixed enemy behavior along the way. No wonder it differed
from the original!
NEWS: Mention INSANE fixes.
HOPKINS: Some renaming in ObjectsManager
HOPKINS: More renaming in ObjectsManager
HOPKINS: Rework OPTI_ONE to make it more readable, rename it
NEWS: Clarify INSANE news item a bit by mentioning Full Throttle

Sure, it was obvious to us, but not necessarily to the reader.
HOPKINS: Remove useless check in loadLinkFile, remove comment. Thanks SylvainTV for pointing it
SCUMM: Hardly-even-worth-mentioning cleanup.
SCI: Add a more generic solution for the problem found in bug #3605269

We now accept signals from all channels if channel 15 is missing. This
is a very rare edge case, but our behavior is now somewhat closer to what
the original interpreter seems to be doing. Mordack's appearance animation
is now synced properly. The more generic workaround works for songs 1840
and 1843, but not for 1849, which is still problematic and we still resort
to manually changing its dataInc selector
NEWS: Fix typo

Thanks, alexbevi
HOPKINS: Fix rendering of French accentuated characters
SCUMM: Add Italian Windows demos of Freddi Fish 4 and Putt-Putt Enters the Game.
HOPKINS: Standardize the use of g_PTRNUL
Properly fix bugs #3267956 and #3605377

SCI: Only stop after fading, if the song to be faded is faded down. Also,
reset the song signal when fading starts. It was set to -1 when fading
started in bug #3267956, thus it stopped immediately.
SCI: Add a hack to fix bug #3596335

Game scripts are waiting indefinitely for a song, thus we change its dataInc
selector to prevent that from happening
HOPKINS: Refactor searchCat to remove the use of g_PTRNUL, add a parameter to clarify the result of the function