Changelog

• #426 Update wapm-cli submodule, bump version to 0.4.1
• #422 Improved Emscripten functions to run optipng and pngquant compiled to wasm
• #409 Improved Emscripten functions to run JavascriptCore compiled to wasm
• #399 Add example of using a plugin extended from WASI
• #397 Fix WASI fs abstraction to work on Windows
• #390 Pin released wapm version and add it as a git submodule
• #408 Add images to windows installer and update installer to add wapm bin directory to path