Adding `color` attr option to `[event_list]` shortcode

Adding `Click Here to Share` buttons for each event

Purging page cache before and after thumbnail generation

Purging page cache when saving event thumbnail

Documenting 1.7.0

Adding `.past-event` based on event End Date

Adding .past-event CSS class and associated styling

Adding `weeks` attr to [event_list/]

Removing comma in minimized file

Documenting 1.4.0