Fixes#325
The linter allows a directive to contain trailing whitespace characters like
\r, but does not trim them before iterating on the rules. As a result, the last
rule in the list contains the trailing whitespace characters and never matches
any existing rule.
I added the necessary trimming, as well as a test with 2 checks to go along
with it.
Mathieu Couette
027d1b0a9a