Create scheduled carousel for home page

[kungfuchicken]

As program director
I need to highlight different programs at different times
So that I can encourage interactions

AC

• a default set of HomepageFeatures are always available
• the default set of HomepageFeatures can be superseded by scheduled features
• scheduled features
  • must have an end-date
  • may optionally have a start date in the future
  • can be set to recur annually