Insufficient funds transaction succeeds

[ekkis]

I recently issued a transaction attempting to send more funds than were available in my wallet, in order to see the transaction fail. it succeeded which puzzled me greatly. I asked about it here:

https://stackoverflow.com/questions/54918074/how-to-tell-if-an-erc20-token-transfer-succeeded/54923014#54923014

...and the answer came back that the transfer method should require() instead of returning false (please see Nikos' reply to the question)

I don't know enough Solidity to implement this or I would offer a PR but it should be fixed