fix(README): fixup formatting of the markdown file

no real content changes at this point. just cleaning up the markdown of
the file first.
fix(README): cleanup the prose in the README

This cleans up the prose in the README file a bit and introduces some
formatting changes.
Merge pull request #16 from philips/cleanup-readme

Cleanup readme
Merge pull request #15 from xiangli-cmu/master

error handling