new branch to fix event_occurences bug. Pivotal #:76544670

new branch to fix event_occurences bug.
Pivotal #:76544670, https://www.pivotaltracker.com/n/projects/982890/stories/76544670
repeating event schedule is not respecting end time limit (event.repeat_ends_on)
Fixes repeating event repeat_ends_on bug by modifying the next_occurrences function to only accept scheduled event instances before that datetime.
When I run db:reset, db:migrate sequence, then this table disappears.  I.e., there's no migration that creates the scrums table.