Add language server for .wat in editor page #240

There's no language server in editor page for .wat currently. Would you like to integrate wasm-language-tools (a language server for WebAssembly Text Format) into that editor? The language server is published as .wasm file to npm and there's no need to build it manually.

Adding language server to there can bring us "hover", "goto definition" and more functionalities on .wat. Here's another project PlayWat whose .wat editor is powered by wasm-language-tools.