fix the creation of workpackages, when a validation-error occurs

added missing :locals to the render-call of create; fixed the
highlighting in the menue for workpackages.
removes "View all work packages" menu item
fixes menu highlighting on issue reports
fixes unit test broken by renaming menu item
Merge pull request #429 from opf/fix/workpackage_create_exception_on_validation_errors

fix the creation of workpackages when a validation-error occurs