Always show payment summary on registration (managers only)

[aavilesd]

Some event managers have reported getting confused with the e-payment working status after setting it on a fresh registration form.

Since the registration form doesn't have any billable field by default, the payment total will be 0 and the payment summary won't be displayed in the confirmation page.

For testing purposes, they are expecting to see the payment summary after registering themselves, but it is missing and it's not clear if it's due to some mistake in the configuration.

Since normal users shouldn't be bothered about it, a good approach would be to always display it for admins only even if the total amount is zero.