Modify examples in README

Change examples to have "Bad" and "Good" headings instead of inline
comments, and split each example into its own code block.

Also removed an extra `HexFormat` section which snuck in.

Change-Id: I53fd6d3b7e68f08400251a9e8fb82911843f8bc9
Reviewed-on: https://gerrit.causes.com/33669
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>