#82 Added validations and modified the tests in students_controller_spec accordingly
#82 Added Semester validation, made first/lastname immutable, made up student's edit view test
updated schema.rb after migrations
Merge commit 'a97a641d3d2c7780f0e19ad52899774bf47e7b7b' into develop-js

Merge of develop branch without the commit causing authentication hickups in tests

Conflicts:
	app/models/student.rb
	spec/controllers/students_controller_spec.rb
	spec/factories/user_factory.rb
raise a not found error, if there is a user with the given id, but it's not a student.
adapted seeds for student field validations
#92 Added Verwaltung to seeds, description still missing
Merge branch 'develop-js' of github.com:tkowark/hpi-hiwi-portal into develop-js
modified the chair seed, so that there are valid deputies
fixed login issue, so that default attributes are present
Merge branch 'develop' of github.com:tkowark/hpi-hiwi-portal into develop

Conflicts:
	Gemfile
#112 added pipes to footer
Merge branch 'develop-js' into develop
fixed some students_controller tests
fixed student_controller test as requested by Lixissimus
Fixing student edit view test and Merge branch 'develop' of github.com:tkowark/hpi-hiwi-portal into develop

Conflicts:
	app/views/students/_form.html.erb
	config/locales/models/student/en.yml
	db/seeds.rb