util: improve unicode support

The array grouping function relies on the width of the characters. It was not calculated correct so far, since it used the string length instead. This improves the unicode output by calculating the mono-spaced font width (other fonts might differ).

I had to move some functions. Otherwise we'd have to load the utils functions by default and that did not seem necessary.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines