Special property "Page creator" and "Page editor" to cater for interwiki user names

[kghbln]

Setup

• MediaWiki | 1.31.0 (b9cc61f)21:41, 1 August 2018
• PHP | 7.0.30-0+deb9u1 (apache2handler)
• MariaDB | 10.1.26-MariaDB-0+deb9u1
• Semantic MediaWiki | 3.0.0-alpha (7b51392) 10:21, 2 August 2018
• Semantic Extra Special Properties | 2.0.0-alpha (6060a7d) 17:00, 16 July 2018

Issue

Starting with MediaWiki 1.31 it is mandatory to provide an interwiki prefix when importing pages from a foreign wiki via special page "Import". This interwiki prefix is being used to reference the foreign wiki's user in the version history of a page. See gerrit commit 386625 for further information on this change.

There are two variations:

• The provided interwiki prefix is unknown to the wiki. In this case only a string like prefix>UserName is used.‎
• The provided interwiki prefix is known to the wiki. In this case a link to the respective URL is used displaying the string like prefix>UserName.‎

As a result the special property "Page creator" is not set due to "User:prefix>UserName" cannot be used as a page name.

This issue is the SESP variant of SemanticMediaWiki/SemanticMediaWiki#3278

Steps to reproduce

See the version history on sandbox (observable for "Page creator") and browsing on sandbox.

[alex-mashin]

And what should the value of the property Page creator be, instead of User:prefix>UserName?