require syck for ruby 2.1 in order to allow migrations to run
Merge pull request #799 from opf/feature/rails21_migrations

require syck for ruby 2.1
render author in planning_element/show
added changelog entry

Conflicts:
	doc/CHANGELOG.md
Merge pull request #791 from opf/fix/no_author_id_in_planning_element_show_3666

render author in planning_element/show