request #7182 - Only allow relevant trackers for BI creation.

Change-Id: I8d5450bd3f8fb58981c95bdae015ba487f72cbf3
Upgrade of plug-in, feature and update site versions.

Change-Id: I0e118c9182e7bd95763d7e62769f64801515707f
request #7228 - Prevent IllegalArgumentException in deactivate.

This error appears in the error log provided with request #7228.

Change-Id: Ie75872d176c23699a8c7cccf455164f278d945bb
request #7228 - Date fields on cards.

Null dates caused severe issues in cardwalls.
Now it's possible to display date fields even if they have no date.
Updating cards with date fiels changed from null to non-null and
vice-versa has been successfully tested.

Change-Id: Iedef9e984f29b6bd72cebe6d6503712994ed5b25
Updated version of plug-ins and feature.

Change-Id: Ifcede3838cb76343597eb2ae742902bf598ee032