Simple jupyter kernel using mlir-opt and reproducer to run passes. Useful for
local experimentation & generating examples. The export to markdown from here
is not immediately useful nor did I define a CodeMirror synax to make the HTML
output prettier. It only supports one level of history (e.g., _) as I was
mostly using with expanding a pipeline one pass at a time and so was all I
I placed this in utils directory next to editor & debugger utils.