adds explicit search route
extracts search form into own partial
fixes search on work package with offset provided
updates changelog
Prevents adding attachables that are removed
Adds changelog entry
soo much whitespace..
Merge pull request #572 from opf/fix/search_next
simplify journal attachment migration
Merge pull request #568 from opf/fix/attachable_migration
Merge branch 'feature/rails3' into fix/activity_atom_feed

Conflicts:
	doc/CHANGELOG.md