~jaro/balkon

ref: 3f953d1a770ba18cdea4bd6e7209969bae6c6819 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.