Moves code from issue.rb into work_package.rb.

This also removes double private declaration from work packages model.
Merge remote-tracking branch 'opf/feature/rails3' into feature/remove-issues

Conflicts:
	app/models/work_package.rb
Fixes the seeds to completely ignore PlanningElements.
Actually remove the code that was previously commented out.
Merge branch 'fix/seeds' into feature/remove-issues
Pulled up several methods over the protected-barrier to make them accessible again.
pulled up some more function that accidentally fell under protected.
avoids leaving User.current set after spec
Fixes timeline view cuke.
Removes obsolete step definition.
Fixes some warnings in the step definitions.
Restores Gemfile.lock from feature/rails3
fixed spec no longer working with my version of rspec
replace deprecated stub! with stub
circumvent mass assignment protection in spec
stubs User.current to avoid spec side effects between specs
fixed unit-test-issues

issues came out of pulling up methods up to work_package and the
wrongly reflected table-names.
Restores Gemfile.lock from feature/rails3
Merge remote-tracking branch 'opf/feature/rails3' into feature/remove-issues

Conflicts:
	db/seeds/development.rb
Merge pull request #421 from opf/feature/remove-issues