Error message needed when you submit no information

[euriehong]

When you hit submit without having any data in the input box or a file uploaded, you should get an error message that reads:

Please enter dbSNP IDs or coordinates into the input box or upload a file to begin your search.

[hitz]

try to fix this for beta release... a similar error if you go to /results/ with no data or invalid session id it throws a stack trace.