~jaro/balkon

ref: 56b3ee16c587863ff45e5564df83cb23905aca90 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.