~jaro/balkon

ref: 07b55a3860ee3d685303213a96c9b7bad0fec7ad balkon/test/Data/Text/ParagraphLayout/Internal d---------
Test removing spaces around lines.
Remove collapsible spaces at beginning of lines.
Allow empty lines when hard line breaking.
Reduce test dependencies on fonts.
Properly use ICU locale identifiers.
Refactor line breaking.
Allow breaking at character bounds.
Implement trimming spaces at end of lines.
Move non-public modules into Internal namespace.