When computing the width of multi-line text, split lines and return the longest

Along with the newline support in Font::write(), Font::getTextWidth() now
splits text along '\n' and returns the width of the longest split.
Fix the bounding box of message boxes

Multi-line message boxes had the incorrect height.

I also took the opportunity to make named constants out of magic numbers
making up the various message box dimensions.
Implement word wrapping as a method of Font

This implementation is based on the implementation in TextDialog::preProcess,
with one major difference: it works on the entire input string, copies it much
less as part of its function, and tries to quickly establish a small search
space for the length of the beginning split of each line.

With most standard fonts and sizes, this means up to 9 computations of metrics
per output line.
Use Font::wordWrap in TextDialog and TextManualDialog

The constructors of those classes now accept a string to be wrapped, instead
of a vector to be modified with split lines inserted into its middle.

Along with this conversion, manuals for applications stored in OPK packages
are now transferred into a string without garbage at the end.
Made text file reading more efficient and robust

Instead of reading the file line by line and then concatenating those
lines, just load the entire thing in one go. And pay more attention to
error conditions.
Wrap long subtitles to multiple lines in Dialog::writeSubTitle

Setting descriptions and help prompts now appear fully even if they are longer
than the screen allows. Translations do not need to worry about allowed text
being wider than the screen in some fonts anymore.
Cap the width of setting names in SettingDialog to the width of the longest

Setting values are now displayed 10 pixels to the right of setting names, as
passed to MenuSetting::draw.

This commit also contains the following cleanups:

* The height of a row is passed to MenuSetting's draw and touchscreen methods.
* MenuSettingRGBA's magic constant (36) to separate the text for a color's
  four components is now a named constant.
* MenuSettingRGBA's color preview squares are now rowHeight - 2 pixels tall,
  and have a white border surrounded by a black border to help view the color
  it contains in both light and dark themes.
* The rectangle behind the selected setting's name is now drawn by that
  setting's drawSelected method.
Changed word wrapping to avoid trailing empty line

If a text file ends in a newline, the previous line splitting code
would append an empty line at the end, which looked odd. So now we
explicitly check that a newline is only inserted if more characters
follow.
Update Norwegian

Complete rewrite of the Norwegian GMenu2X for GCW0.

Done by: Lithium Flower
Removed ChangeLog

It is not maintained. Please read the Git log instead.
Use a single "about.txt" for all platforms

The content of this file is not actually platform specific, so having
it in multiple locations is just an extra maintenance burden.
Update translation credit for Norwegian
Make a pro-forma ChangeLog file

Automake considers an absent ChangeLog to be fatal.