Show "Result submitted" persistently to avoid duplicate submission

[corriekwan]

"Result submitted" message is on a pop up right now, and can be easily dismissed. As the pop-up get dismissed, users forget if they have submitted the lunch fund entry and potentially re-submit it .

Solution 1: Put "Result submitted" directly on the Lunch Fund submission UI, so it cannot be dismissed until user closes the UI.

Solution 2: Avoid duplicate entry. Eg. Disable "submit" button unless fields get changed on the UI.

Solution 3: Let your imagination go wild. :)

[kendrickw]

Added the infrastructure to detect duplicate submission now. Can actually implement this feature completely in UI now.

[kendrickw]

Solution 2 implemented.