bug: fix some issues with early version of whatsminers, and handle some possible errors with BOS.

pyasic/miners/backends/bosminer.py

@@ -1043,7 +1043,7 @@ class BOSMiner(BaseMiner):
             if data == "50":
                 self.light = True
             return self.light
-        except TypeError:
+        except (TypeError, AttributeError):
             return self.light
 
     async def get_nominal_hashrate(self, api_devs: dict = None) -> Optional[float]:

pyasic/miners/backends/btminer.py

@@ -442,7 +442,8 @@ class BTMiner(BaseMiner):
 
         if api_summary:
             try:
-                return api_summary["SUMMARY"][0]["Power"]
+                wattage = api_summary["SUMMARY"][0]["Power"]
+                return wattage if not wattage == -1 else None
             except (KeyError, IndexError):
                 pass