* initial const prop attempt
* added support for broadcast ops
* adde all binary broadcast ops into custom builders with precise type
* added test example
* working
* format
* fixed suggestion by Tung, start woring on unary
* added subtraction and neg the right way, and added elementwise mul too
* formatting changes
* format
* format
* added instructions to add new optimizations
* Setup documentation server, move doc files from /doc to /docs as per Github Pages convention.
* Include deleted files in patch.
* /doc -> /docs
* /doc -> /docs
* Update documentation on importing ONNX spec into ONNX Dialect; provide documentation on how to add new documentation pages.