core: Add templates to the return value of query

Adding templates to the Map of GetTemplatesFromExportDomainQuery, once
they parsed from the OVF.
This query is being called when the user wants to view the list of
templates in the export domain.

Change-Id: I3af09baee674814418b00254fcf65f48b3961d28
Signed-off-by: Maor Lipchuk <mlipchuk@redhat.com>