convert restart_required to 'true' or 'false' string

The output of the configuration-parameters-list/show was
inadvertently changed when the parameters were moved into
the database in Juno.

Change-Id: Ic7d215482f5a9ab8ba2059cae7b91a99b35f2795
Closes-Bug: #1379665
Merge "convert restart_required to 'true' or 'false' string"