load and authorize resource for Admin/Grading Method
[fix] validation method was symbol
Extract personal fields from models in Person module
[migration] Add gender and birth_date fields to guardians table
Begin to use shared partials for person fields and form_fields
Add shared_examples_for: notable, addressable, contactable, thrashable
Create Teacher model
Basic teachers views and controller
[spec/requests] teachers_spec
[spec/requests] Extract commute_methods_spec from students_spec
[spec/requests] Extract class_group_enrollments_spec from students_spec
[spec/requests] Fix student_achievements_spec
[spec/requests] teachers/images_spec
Clean students_controller
[menu] Add Teachers
[menu] Edit
[helper] Fix th_actions from html_helper
[views] Create gaku/shared/picture and upload_picture partials
Create Picture module and it_bahaves_as avatarable
[spec/requests] Rename images_spec to picture_spec in students and teachers