Revert "Revert pull request#220"

Pull request #220 was reverting temporarily because it wasn't compatible
with the current app using it.

This reverts commit 7879185997f0788dbfe8e90ea09bf3bbe742424f.

Conflicts:
	Gemfile.lock
	lib/lims-core/version.rb
Fix JRuby specs.
Make Action#user read only.
Make Action#user read only.
Merge pull request #221 from maxigit/60174706_get_the_user_from_the_request_header

60174706 get the user from the request header
Merge branch 'development' of https://github.com/sanger/lims-core into development
Add Session#with_subsession.
cache.

Object don't have to be 'to save' anymore to be considered as managed.
Merge pull request #223 from maxigit/61029592_use_global_session_within_lims-api

Add Session#with_subsession.
Creating revision tables and tables
Audit Tables migration works with triggers and view.
Create SQL session row within Store#transaction.

Needs to be moved somehow in session.
Remove exception at the end of audit migrations.

This exception was there to be able to rerun the transaction if
there were some problems.
Create session object within session.
Change appliction_id to backend_application_id for session object.
Bump version
Merge pull request #226 from maxigit/23721027_investigate_audit_and_session

23721027 investigate audit and session