Interviewer Pause Endpoints

Added user.createInterviewerPause endpoint to create an interviewer pause for a user. While paused, the user will not be scheduled for interviews.
Added user.listInterviewerPauses endpoint to list all active or scheduled interviewer pauses for a user.
Added user.deleteInterviewerPause endpoint to delete an interviewer pause.
Added isPaused field to the qualifiedMembers and trainees arrays returned by interviewerPool.info to indicate whether each member is currently paused from interviewing.