Fakevim highlight matching is unreadable when using a dark colorscheme

If you are using a dark colorscheme, and do a search for text, the highlight (background) color can match the foreground (text) color, making the text completely disappear.

In the void FakeVimHandler::Private::highlightMatches(const QString &needle) function, the background color is set, but not the foreground color:

sel.format.setBackground(QColor(177, 177, 0));

I changed this color to be more readable, and added the foreground color change as well:

sel.format.setBackground(QColor(151, 113, 255));
sel.format.setForeground(Qt::black);

Ideally, these colors should be set from the colorscheme itself, rather than being hard coded, but until then, this is a quick fix.