Header text isn't visible enough due to light background

As per "Image protection" (https://www.google.com/design/spec/style/imagery.html), light text should have dark background to be visible enough. I've already fixed the issue by adding a dark gradient to the header layout, and I request a branch merge. Sorry if I did something wrong, this is my first commit to an open-source project.

mentioned in merge request !12 (merged)

Status changed to closed

Status changed to reopened

mentioned in commit 8809f4cc

Status changed to closed

Milestone changed to 2.2.5

Added Bug label

Reassigned to @Jawnnypoo

Will be in next release