CLC-4568 - Added current_score and current_grade to grades served by Canvas::Egrades#canvas_course_students
CLC-4568 - Updated Canvas::Egrades#official_student_grades_csv to support 'type' argument
CLC-4568 - Added support for 'type' parameter in CanvasCourseGradeExportController#download_egrades_csv
CLC-4568 - Created two buttons for current and final grade download options. Applied grid layout and styled form appropriately in E-Grades LTI tool