Updates to TeacherCandidate and related entities

Story 

With idea of further alignment with Ed-Fi core and use of the person model TeacherCandidate (and related entities) will be updated in v1.0 with the following changes:

• Renamed TeacherCandidate to Candidate, related sub elements that were part of teacher candidate (TeacherCandidateIdentifier, TeacherCandidateIndicator have also been renamed to remove the Teacher moniker)
• Removed reference to student (reference should be made through person reference)
• Removed TeacherCandidateAcademicRecord removed, use StudentAcademicRecord instead
• Removed TeacherCandidateCourseTranscript, use StudentCourseTranscript instead
• Removed CompleterToStaffAssociation, this relationship should be determined through the person reference
• Added CandidateCharacteristic have been added
• Added an optional reference to application
• Removed education organization reference, use CandidateEducatorPreparationProgram reference instead

TeacherCandidateStaffAssociation

• Renamed to CandidateRelationshipToStaffAssociation
• Added StaffToCandidateRelationshipDescriptor to describe the relationship between Staff and Candidate