Bugs

• Prevent color palette in small PNGs (caused scrambled display of small icons under some conditions).
• Fixed Windows DIB creation for ICO (caused scrambled display of small icons under some conditions).
• Fixed wrong offsets/sizes for PNGs in ICO.
• Fixed non-quadratic images in ICNS.

Changes

• Added sizes is32and il32 to ICNS.
• Added special ICO format for Windows executables.
• Noticeably faster rescaling due to inlining interpolate functions.
• Much faster ICNS generation due to caching of icon chunks with the same size.
• Added much faster alternative bicubic rescaling (should work although not thoroughly tested).
• Removed dependcy from pako.
• Add missing TypeScript definition files.
• Use ES2015 (TypeScript).