Version 1.9

Changes:

• "sounds:play" now returns handle & sound file name string
• added "sounds:stop" wrapper function for "core:sound_stop"
• added setting "sounds.enable_tests"
• added sounds testing formspec shown with "/sounds_tests" chat command
• added localization support for sounds testing formspec
• added Spanish translation for sounds testing formspec
• added sounds:
  • ar_fire
  • fireball
  • laser
  • pistol_cock
  • pistol_fire
  • pistol_fire_dry
  • pistol_reload
  • ricochet
  • rifle_cock
  • rifle_fire
  • rifle_fire_cock
  • rifle_fire_dry
  • rifle_small_fire
  • shotgun_fire_pump
  • shotgun_pump