Fix PSCreatePageJob if no "linked form" is set

Based on a patch from @WolfgangFahl.
Merge pull request #595 from yaronkoren/patch-1

Fix PSCreatePageJob if no "linked form" is set
Update README.md

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Update README.md

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Update docs

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Add ValueDescription::getProperty

https://github.com/SemanticMediaWiki/SemanticMaps/issues/28
Merge pull request #597 from SemanticMediaWiki/valuedesc

Add ValueDescription::getProperty
ValueConditionBuilder to return FalseCondition for non-supported DataItem type

- `SMWDIGeoCoord`
- `SMW\DIConcept`

Avoids an exception for when `null` is returned which surfaced during the encounter with [0].

[0] https://github.com/SemanticMediaWiki/SemanticMaps/pull/29
Merge pull request #598 from SemanticMediaWiki/valuecond-falsecond

ValueConditionBuilder to return FalseCondition for non-supported DataIte...
Update RELEASE-NOTES.md

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Report min as well

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Merge branch 'master' of ssh://wmfgerrit/mediawiki/extensions/SemanticMediaWiki