Furnace v0.6pre14 (beta) - The Freeze

aaaaaaand still frozen

changelog

• implement MSM6258 VGM export
• fix a typo in the error message that appears when you load multiple samples at once and one or more fail to load
• discourage use of Pong
• Sound Unit: fix getPan() again
• C219 fixes
  • fix lack of phase reset macro
  • fix noise being restricted by sample length and therefore being unusable in certain circumstances
  • don't phase reset if the duty macro hasn't changed
• add a sample rate table to MSM6258 chip config
• four more demo songs (by Yuzu4K and TheDuccinator - thanks!)
• documentation updates