Fix typos, whitespaces, updated [System]

It seems that there isn't a l10n system for System Information.

btw, what are those files in the ppsspp source tree for?
> chinese.txt
> korean.txt

They seem useless.

P.S.: Is there something like a font fallback feature inside the program? Will it be added?
P.P.S: What should we use for the font name? Localized Unicode name as displayed in the Fonts menu or the name as used in CSS?