~jaro/balkon

ref: 81d758baf4c7f7ab803edccb4dd1bb7e82a4753d balkon/test/Data/Text/ParagraphLayout/Plain d---------
Test ultra narrow Arabic text.
Deprecate the Plain interface.
Add user data to spans.
Qualify Plain interface.
Future-proof records with options.
Qualify Plain ParagraphData.