sendPayment 
  suspend fun sendPayment(destinationPublicKey: String, amountMsats: Long, maxFeesMsats: Long, timeoutSecs: Int = 60): OutgoingPayment
Sends a payment directly to a node on the Lightning Network through the public key of the node without an invoice.
Return
An OutgoingPayment object if the payment was successful, or throws if the payment failed.
Parameters
destinationPublicKey  
The public key of the destination node.
amountMsats 
The amount to pay in milli-satoshis.
maxFeesMsats  
The maximum amount of fees that you want to pay for this payment to be sent. As guidance, a maximum fee of 15 basis points should make almost all transactions succeed. For example, for a transaction between 10k sats and 100k sats, this would mean a fee limit of 15 to 150 sats.
timeoutSecs 
The timeout in seconds that we will try to make the payment.
Throws
if the payment failed or if the wallet is locked.