~jaro/balkon

ref: 904bd77ec7a8460971bec4a592629ee74c8aec3f balkon/test/Data/Text/ParagraphLayout/Internal/TextContainerSpec.hs -rw-r--r-- 3.3 KiB 
Move non-public modules into Internal namespace.

Minimise working with Data.Text.Internal.

Implement run splitting.