Fixed account exists query

Since we are searching by username, filtering of the users must be done
client side.
Correctly identify the personal tenancies
Fix dependency on tenant manager role

Allow the import to work even if there is no tenant manager role.
Use IPD saml key as name if mapping is blank

If the IDP doesn't exist in the mapping table, the idp's saml identity
can be used as the name.
Re-enable all parts of import steps
Fixed invalid reference to old JSON field