Mul language

For a lot of instances multiple languages typically have identical labels and descriptions.

As a consequence Wikidata has storage and performance problems with redundant labels and descriptions, taking up storage and memory.

• Names of persons, firstnames, lastnames → labels only to be stored for the mul language (no description); the same for aliases
• Descriptions of instances of firstnames, lastnames → should be not be stored; to be retrieved at runtime from the instance language label

• Item creation, item update
• Retrieval of labels
• Pywikibot scripts
• Personal Babel registry

• Only the mul-label is stored (Wikidata)
• Do not store obvious item descriptions (Phabricator)

• Inverse statements
• Derived statements