[controller] load departments and allow params for department_id in specialties
[model] add department associations
[spec/model] department associations
[views] add department fields
[migrate] add deparment association to specilaties
[spec/request] test deparment selection in specialties
[controller] load departments in syllabus controller
[views] add depratments to syllabus
[model] department syllabus assoc
[spec/model] deparment syllabus assoc
[migrate] add deparemnt reference to syllabus
[spec/feature] test department selection
Merge pull request #238 from Genshin/add_departments_to_syllabuses

Add departments to syllabuses
Merge branch 'master' of github.com:Genshin/GAKUEngine

Conflicts:
	core/app/models/gaku/department.rb
	core/spec/models/department_spec.rb
[controller] add department to exams
[view] fields for showing department in exams
[model] department exam assoc
[spec/model] department exam assoc
[migrate] add department_id in exams table
[spec/request] test behavior of department to exams and exams assigning syllabus department