Release 7.8.0
Includes the following merges:
- PR #307: Fix, document, and test get_rltt and get_schedule_stop_time
- PR #302: Add email notifications for validation violations
- PR #305: Change limits in SPM and off-nom-roll validators to fix violations
- PR #304: Update code and tests for use with ska_sun accurate position
- PR #301: flatten namespace package names
- PR #295: Use cached property in commands validation