seeded JobOffers

by running rake db:seed all JobOffers are deleted and 2 fake Jobs are entered.
refactored programming language call in view

view does not access directly the model, but gets the Programming languages by the controller
improved job offers form design
Merge remote-tracking branch 'origin/develop-ja' into crud-job-offers
reader navbar on top
added paperclip url instead of gem
try to avoid deploy error
added dpl gem
changes of last commit also in Gemfile.lock
Merge remote-tracking branch 'origin/develop-ja' into crud-job-offers

Conflicts:
	db/seeds.rb
Reverted changes
added model test for search #8
added language to job offer
improved job offer design
added controller test for sort
removed job offers from seed
Merge remote-tracking branch 'origin/develop-ja' into crud-job-offers

Conflicts:
	db/schema.rb
added job offers to seed