Fatal error for invalid input.

[jfjlaros]

Multiple interfaces crash when the SNP converter is called with 'rs0000' as parameter. Both the website as well as the batch checker seem to be affected. The webservice seems to handle this problem fine.

To reproduce:

• https://mutalyzer.nl/snp-converter?rs_id=rs0000
• Run the SNP batch converter with a single line containing 'rs0000'.