Fix some formatting in linter README

One of the tables had an extra row, and one of the code examples did not
have any syntax highlighting. Fix both.

Change-Id: Ie653491af926de58d88edd31511f4c48d51444ba
Reviewed-on: http://gerrit.causes.com/36700
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>