waitblockheight timeout causes crash.

[fiatjaf]

Issue and Steps to Reproduce

If we send a payment with pay and the receiver return an incorrect_or_unknown_payment_details with a fake height like 999999 pay will call waitblockheight, but since that block height won't be reached within the timeout window, it will crash with:

pay: Unexpected result from waitblockheight: {"code":-1,"message":"Timed out."}

Instead it should just abort the payment.

getinfo output

{
   "id": "02c16cca44562b590dd279c942200bdccfd4f990c3a69fad620c10ef2f8228eaff",
   "alias": "@lntxbot",
   "color": "296683",
   "num_peers": 29,
   "num_pending_channels": 1,
   "num_active_channels": 23,
   "num_inactive_channels": 0,
   "address": [
      {
         "type": "ipv4",
         "address": "5.2.67.89",
         "port": 9735
      }
   ],
   "binding": [
      {
         "type": "ipv4",
         "address": "0.0.0.0",
         "port": 9735
      }
   ],
   "version": "v0.9.2-77-g23d4e53",
   "blockheight": 664387,
   "network": "bitcoin",
   "msatoshi_fees_collected": 31959529,
   "fees_collected_msat": "31959529msat",
   "lightning-dir": "/home/fiatjaf/.lightning1/bitcoin"
}