Match the Native iOS Keyboard Size and Key Colors

@Zoltán I measured both over grey, blue, red and dark apps: the stock keyboard adds light to whatever is behind it, so its keys come out pure white over grey and tinted over color, and a third-party keyboard isn't allowed to draw that way. The current shade is the closest I could get across all four; full white would only match on grey and be further off on the rest. The keys themselves are the same size as stock, the extra height is the suggestion bar, so you can shrink everything with Keyboard height or hide the bar under Bar in settings.