Language file adjustments and arrows for direction keys (*u, *d, *l, *r).

* All languages except Chinese: Remove redundancy in the New game menu. Remove "from the card".
* All languages except German and Chinese: Remove "games" in "recently played games". It's implied by the rest of the menu.
* Spanish: menu should be menú.
* All languages: modify keys in the screenshot slideshow message so that direction keys are arrows.
* Tools/Screenshots, English, French, Spanish: Stop implying that you can browse the screenshots; instead imply that it's a slideshow you control only sequentially.
* Dutch: Try to shorten "Ga terug naar het spel" so it can fit in a button, by removing the "Ga". It still splits.