Translatable trek published field (ref #1003)
Show translated checkboxes (ref #1003)
Add null to published field (ref #1003)
Add publication date field (ref #1003)
Show translated publication status in trek detail page (ref #1003)
Add flags for trek detail (ref #1004)
Allow to see the trek in the different published languages (ref #1003)
Update changelog (fixes #1003)
Fix default published status to be False instead of None
Merge branch '1003_translated_publication' into develop

Conflicts:
	CHANGES