v2.0 preview 4

Still work in progress, expect bugs

Windows download. Other platforms require manual installation of dependencies for now.

Added since 2.0 preview 3:

• Added deduplicate range option, defaulting to 1 (old preview default = infinite, which is now -1. blur 1.8 default = 1)
• Added deduplicate threshold option, defaulting to 0.001 (same as the old default)
• Added scene detection when deduplicating
• Raised timescale slider limits to 2
• Fixed rendering getting stuck on 'Initialising render'
• Fixed config screen crash when using fixed interpolation fps
• Fixed dropdowns rendering off screen
• Add warning when timescale is on and -c:a copy is in ffmpeg override string
• Animate checkboxes when their checked state changes but they weren't clicked
• Fix edge case crash when switching screens