Rename EventBase.status to EventBase.event_status,

[sam-mi]

Event.status fieldname clashes with Django Model Utils Model.status field making subclasses of ls.joyous EventBase incompatible with any project that already implements Model Utils StatusField in their models.

This non-breaking change renames the EventBase.status property to EventBase.event_status and updates references to that field in templates and tests so that the clash no longer occurs.

[linuxsoftware]

Thanks for the PR. I have created Issue #35 to track this.