[JENKINS-24834] CPP check report background colours not displaying for new or resolved issues since upgrade

- White background color was set to all TD elements in core's JENKINS-24625 which overwrote settings of outer TR.
- Missing mandatory "title" element added to l:layout.
Merge pull request #25 from mixalturek/master

[JENKINS-24834] CPP check report background colours not displaying for n...