This adds a basic repl-like console webpage that can be used for
testing of the local pyodide install.

It removes the broken examples based on standalone iodide.

Automatically rebuild packages if any patches or extra files change

Clean up the downloaded file if it's corrupted

Fix #332: Make pyproxy.apply work

Add a mkpkg tool to make new packages.

Fix #327: Add sympy support

Build the _decimal C module.

Fix #316: Add convenience function for converting from nested Arrays

Fix matplotlib wasm backend after undefined attribute behavior changed

Handle numpy scalars in python2js_buffer

Fix conversion from jsproxy to dict

Update for new Iodide renderer API

Webworker support. Fixes issue #246