Update ConceptPage.php

Also provide time of last update
Update en.json

Add time variable
Update qqq.json

Add description for extra value time
Merge pull request #592 from SemanticMediaWiki/554

Enhance concept pages (issue 554)
Update RELEASE-NOTES.md

Add a note about https://github.com/SemanticMediaWiki/SemanticMediaWiki/issues/554
Move to CompoundConditionBuilder

Build a compound condition as the combination of two or
more conditions linked by a logical operator.
Add ConditionBuilderStrategyFinder
Add ValueConditionBuilder

- Move code from CompoundConditionBuilder to ValueConditionBuilder
- Add ValueConditionBuilderTest
- Add ConditionBuilderStrategyFinderTest