Also, make it clearer what is shared and instance-specific

So,
libvlc_t ==> libvlc_global_t
vlc_t ==> libvlc_int_t (internal instance)

p_object->p_libvlc ==> p_object->p_libvlc_globale
p_object->p_vlc ==> p_object->p_libvlc

VLC_OBJECT_VLC ==> VLC_OBJECT_LIBVLC

And by the way, there is some cleanup required :) (ie, some things are created in the global object instead of the instance-specific one)

I was actually trying to understand why command line option parsing on my computer with self compiled VLC behaves as "If the first character of optstring is '+' or the environment variable POSIXLY_CORRECT is set, then option processing stops as soon as a non-option argument is encountered." while neither of these conditions is true (see the while( getopt_long( ... ) != EOF ) loop).
Small illustration:
./vlc -vvv -I dummy input.ts --color
All options before the first non option argument work as expected (-vvv and -I dummy). All options after the first non option argument are also interpreted as being non option arguments.
Help would be appreciated.
(I've already had reports of other people having the same kind of issues)

deserializing floats from configuration (fixes #589)

I know this is NOT the “right” way to fix this.
The “right” way would be to remove floats from the configuration...
but there are approximately one float parameter in the core and 46 ones
in our current plugins set, none of which I use myself. So I am
defintely not going to rewrite all^H^H^Hany of them.

Of course, it would be cleaner to be “strict”  in what we write to
the configuration file, than “liberal” in what we accept... but IMHO,
it is way easier and more robust to be liberal in what we accept in
this particular case (ie. accepting both decimal separators is trivial,
while serializing float numbers manually is complex).

- fix load/save of configuration and creation of configuration directory (refs #528)

vlcrc file. This might seem obvious, but many people on the forums don't
seem to understand that.

    __ppc64__ (meaning PowerPC).

   that under Win32 psz_homedir points to Application Data directory
   whereas psz_homedir points to the user's directory.
 * modules/control/http/util.c: When the target charset isn't UTF-8,
   manually convert Unicode quotes to ASCII quotes (yes this is ugly
   but libiconv doesn't handle it).

 * modules/control/http.c: New RPN functions :
   - 'module' vlc_config_save ('module' can be an empty string) returns status
   - vlc_config_reset

   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)

(da big courmischage)

* standard.c: sap-ipv6 is no more used

configuration.[ch]: Handling of deprecated options in the command line. Add a new configuration helper add_deprecated( name, b_strict).
gui/*: Don't show deprecated option in the preferences
libvlc.h: add the deprecated options from NEWS. Is there others ?
Could the Mac and BeOS dev, check for their gui, please.
Closes #112

* src/misc/configuration.c, ALL: support for auto-saveable config options (saved automatically on exit).

Fix command line parsing

* Each module can declare a "human-readable short name" with set_name
* Modules are sorted by category (set_category, set_subcategory).
  Modules configs can be separated by set_section()
* Separated audio-filter and audio-visual
* Separated extraintf and control
* New command and widget : add_module_list() for comma-separated modules
* Vfilters now use "," as separator

* configuration.c: don't crash on NULL values