Fix black colored text in suggestions when activated with keydown

bug also happens simply when typing to add a new site link, with no keydown.

Fix appears to be to apply color: black only to  .ui-suggester-list a
and not to .ui-suggester-list .ui-ooMenu-item a

Bug: 68386
Merge pull request #89 from wmde/blacksuggestertext

Fix black colored text in suggestions when activated with keydown