- Fix local charset detection that broke (From|To)Locale

Found a simpler way to send an empty picture to the client. It fixes also memleaks introduced in 12196.

Send an empty subpicture to remove the OSD menu on the client application when "menu off" commands is given on the rc interface.

Bug reported by Thomas Knauer

It's already set to C globally because there are a bunch of things that
assume US-style float numbers formatting (config file, RTSP VoD server
to name a few) -- see SetLanguage() in libvlc.

If you want to get a float from the user, you can look for the comma
and replace it with a dot before parsing. However keep in mind that the
stream output parser already uses the comma to separate options; that's
yet another reason to use the dot in any case.

Also, I don't know if some remote locales use neither dot nor comma as
their decimal point.

   not been set to VLC_FALSE yet, the program number is not specified,
   and we're reading a PMT.

, but still miss the other one.

Anyone with Visual Studio here ?

   missing. Beware that this change configuration saving output (it used
   to be saved in users locale).

   this should fix float config options save/load rounding issues. If someone
   has a better fix, feel free to do so (but please dont revert a commit and
   provide no alternative fix)

Reworked OSD Volume handling and display of volumebar. Run make stamp-api to update include/vlc_symbols.h.

may close #163

Use ALSA or tell aRts to use ESD and use ESD in VLC, or fix it.

Change locale (LC_NUMERIC) in appropriate places so we always use the
user's locale when reading/writting floats to config (otherwise it would
read floats using C locale (float separator is . in C) and write them
using the user's local (float separator can be , instead of .))

If these changes aren't ok, then i think that the only solution would be
to always setlocale(LC_NUMERIC, "C") when handling config str<->float
conversions.