Update SMW_LanguageDe.php

Adding special property "query duration"
Update SMW_LanguageAr.php

Adding special property "query duration"
Update SMW_LanguageArz.php

Adding special property "query duration"
Update SMW_LanguageCa.php

Adding special property "query duration"
Update SMW_LanguageEs.php

Adding special property "query duration"
Update SMW_LanguageFi.php

Adding special property "query duration"
Update SMW_LanguageFr.php

Adding special property "query duration"
Update SMW_LanguageHe.php

Adding special property "query duration"
Update SMW_LanguageId.php

Adding special property "query duration"
Update SMW_LanguageIt.php

Adding special property "query duration"
Update SMW_LanguageNl.php

Adding special property "query duration"
Update SMW_LanguageNo.php

Adding special property "query duration"
Update SMW_LanguagePl.php

Adding special property "query duration"
Update SMW_LanguagePt.php

Adding special property "query duration"
Update SMW_LanguageRu.php

Adding special property "query duration"
Update SMW_LanguageSk.php

Adding special property "query duration"
Update SMW_LanguageZh_cn.php

Adding special property "query duration"
Update SMW_LanguageZh_tw.php

Adding special property "query duration"
Merge pull request #131 from kghbln/master

Add special property "query duration" to the language files