ManagedSubject: Fails when deleting expired 2-Step logins

This commit corrects an error with expired 2-Step logins causing
data cascade exceptions (re-save) in the hibernate stack that where
not present in initial testing.

At the same time this tweaks logging slightly to better show what is
going on in production.
Merge commit '94bed8e2e3d61bb73670dd4946637b8e58c225dd' into code-develop - fix TwoStepSession delete problem.

Get the fix for the problem with deleting expired TwoStepSessions.
Bootstrap: add description field to ApiSubject constructor

To workaround the constraints on ApiSubject.description:
  description nullable:false, blank: false

Set the description to reflect this is the Shibboleth IdP API account.
Merge branch 'develop-fix-bootstrap' into code-develop
Merge branch 'code-develop' into tuakiri-develop