Fix README.md development documentation links (#356)
Fix README.md development documentation links (#356)

Now that we have our documentation on Github pages, this fixes the
links to the development documentation, which otherwise would 404 as the
pages no longer exist!

Co-authored-by: XAMPPRocky <6ba45292a2270275b065ccb8b5a1b00bba5fbcfb@users.noreply.github.com>
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