v2.0 preview 5

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

Added since 2.0 preview 4:

• Added config validation
• Fixed scrolling in vertically centred containers
• Fixed YV12 blur error #136 (comment)
• Added stop render button
• Added update checking
• Added the ability to open the output folder on click of the 'render success' notification
• Much improved text inputs
• Added error copying for config preview failed renders
• & more minor stuff

Please create an issue for any minor bugs or suggestions you have. Pretty close to release now.