Logging with loguru (#708)

* logging

* requirements

* add loguru dependency

* restore it

* add loguru

* set log level in .env file

* remove service fee print

* set log level

* more logging

* more logging

* more logging

* pyament.checking_id

* fix

lnbits/extensions/splitpayments/tasks.py

@@ -1,6 +1,8 @@
 import asyncio
 import json
 
+from loguru import logger
+
 from lnbits.core import db as core_db
 from lnbits.core.crud import create_payment
 from lnbits.core.models import Payment
@@ -34,7 +36,9 @@ async def on_invoice_paid(payment: Payment) -> None:
     amount_left = payment.amount - sum([amount for _, amount in transfers])
 
     if amount_left < 0:
-        print("splitpayments failure: amount_left is negative.", payment.payment_hash)
+        logger.error(
+            "splitpayments failure: amount_left is negative.", payment.payment_hash
+        )
         return
 
     if not targets: