Improvements
Improvements grades
Bug prevention
Model fix
link_to_function => button_to_function
Improvements
gerador de contratos
Merge branch 'dev_thiago' of https://github.com/thiagorpp/viamundi into guided_tour

Conflicts:
	app/controllers/grades_controller.rb
	app/views/grades/show_student.html.haml
	app/views/students/show.html.haml