Kill defaults in PSC#scheduled_activities_report.  #3662.

The events API needs to be able to make queries that are otherwise
blocked by defaults.  Two examples of queries that are blocked by
defaults:

1. a scheduled activity report not filtered by state
2. a scheduled activity report whose end date is unspecified
Merge pull request #180 from NUBIC/feature-3662-eliminate-sar-defaults

Kill defaults in PSC#scheduled_activities_report.  #3662.