Convert bylaws to Markdown format and update README

Because ODT is a binary file format, I converted the contents of the document into the plaintext Markdown, which is more accessible and has some fancy adjustments like internal links. I also made some minor inconsequential changes to the bylaws (e.g. change Science & Technology Wing -> Science and Technology Wing) that should not affect the actual terms dictated by the bylaws at all.

I also updated the README with instructions on how to contribute.

Proposed by: Daniel Ge <dange>