Show error message when 'saving' a null/0 set of TLD prices

[bobbravo2]

https://mycircletree.com/client-area/ct-admin/supporttickets.php?action=viewticket&id=5765

When there are 0 results to be updated on pressing save, show an error message.

There are 2 error states:

1. There are 0 checkboxes checked, resulting in the error message "Please use the checkbox to select the TLDs you'd like to import"
2. There are checkboxes checked, but they are already imported into WHMCS. Resulting error message "There 0 new TLDs to import, to overwrite the pricing already in WHMCS, please use the checkbox"

[bobbravo2]

@anatoliyrazin there is still case 2.

[anatoliyrazin]

additional notes:

1.1 Save button push works for all records user put numbers whether checkbox selected or not. This behavior does not make any sense with the fix I added previously. I assume we have to fix the bug and save only for those records the check boxed selected

[anatoliyrazin]

2.1 Overwrite check box affects only Preview button and has nothing to do with Save button. Need to discuss and clarify the issue 2.