bytearray needed write8 and writeRaw8 on esp8266

http://forum.micropython.org/viewtopic.php?p=10559#p10559

bme280.py

@@ -97,13 +97,15 @@ class Device:
 
     def writeRaw8(self, value):
         """Write an 8-bit value on the bus (without register)."""
-        value = value & 0xFF
-        self._i2c.writeto(self._address, value)
+        buf = bytearray(1)
+        buf[0] = value & 0xFF
+        self._i2c.writeto(self._address, buf)
 
     def write8(self, register, value):
         """Write an 8-bit value to the specified register."""
-        value = value & 0xFF
-        self._i2c.writeto_mem(self._address, register, value)
+        buf = bytearray(1)
+        buf[0] = value & 0xFF
+        self._i2c.writeto_mem(self._address, register, buf)
 
     def write16(self, register, value):
         """Write a 16-bit value to the specified register."""