jobs can now be closed by a research assistent (#66)
* added model for job status (simpler solution than maintaining string symbols in the db)
* fixed some issues with spec tests
* fixed bugs
* fixed translation issues
Merge remote-tracking branch 'origin/develop' into develop-ak

Conflicts:
	app/models/job_offer.rb
	app/views/job_offers/_form.html.erb
	app/views/job_offers/show.html.erb
	config/locales/views/job_offers/de.yml
	config/locales/views/job_offers/en.yml
	config/routes.rb
	spec/controllers/job_offers_controller_spec.rb
added a new test for job offer completion
tests for #59
Editing Chairs for admins, including changing the deputy
implementation for #59
Merge branch 'develop-ak-accept-student' into develop-ak
fixed a problem with broken schema file
Email for deputy added
missing files added
Label for Deputy Select in Chair Form
added feature tests for #64
Merge branch 'develop-ak' into develop-ak-approval-of-the-head-of-chair

Conflicts:
	spec/features/job_offer_pages_spec.rb
finished new job offer email service for the deputy
first features for #64 added
Merge branch 'develop-ak-approval-of-the-head-of-chair' of https://github.com/tkowark/hpi-hiwi-portal into develop-ak-approval-of-the-head-of-chair

Conflicts:
	app/controllers/job_offers_controller.rb
	spec/features/job_offer_pages_spec.rb
pending job offer should be redirected to the index page test fixed
testing...