~jaro/balkon

ref: 4ef7aad8fe112d65d4b366f2132c68bb2f054dd5 balkon/.golden/lineHeightSmaller d---------
Add ignored prefixes and suffixes to test data.

This ensures that implementation does not rely on the texts having zero
offset inside their byte arrays.
Use top edge for placing lines.
Implement absolute line heights with half-leadings.