check all directives in batch block until recreate selected

check all directives in batch block until recreate selected

Fixed regression in batch mode due to :ticket:`883` where the "auto" mode
of batch would fail to accommodate any additional migration directives
beyond encountering an ``add_column()`` directive, due to a mis-application
of the conditional logic that was added as part of this change, leading to
"recreate" mode not being used in cases where it is required for SQLite
such as for unique constraints.

Change-Id: I6315569caff5f3b33d152974ebecc8b18d9cc523
Fixes: #896