* ./configure.ac.in: duplicated arguments to AM_INIT_AUTOMAKE to fix

  * ./configure.ac.in: duplicated arguments to AM_INIT_AUTOMAKE to fix
    locales breakage.
  * ./src/libvlc.c: libvlc understands the VLC_VERBOSE environment variable,
    to be set between 0 and 4. Default value is 0 for a program using libvlc,
    but vlc sets it to 1 by default.
  * ./src/misc/configuration.c: -v now works the old way (-v, -vv, -vvv) as
    well as the new way (-v0, -v1, -v4). -v1 is the same as -v, and -v0 is
    the same as -q (quiet). Hope it's all understandable.