~jaro/balkon

ref: ce4f4845a30de2bbcbce4c8c9eb2a0607b57588d 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.