Add temperature offset to utemp

utemp.yaml

@@ -18,6 +18,12 @@ esp8266:
 preferences:
   flash_write_interval: 15sec
 
+globals:
+  - id: temperature_offset
+    type: float
+    restore_value: true
+    initial_value: "0.0"
+
 logger:
   level: INFO
   baud_rate: 0
@@ -65,7 +71,27 @@ sensor:
     temperature:
       name: "Temperature"
       oversampling: 16x
+      filters:
+        - offset: !lambda return id(temperature_offset);
     pressure:
       name: "Pressure"
     address: 0x76
     update_interval: 15s
+
+number:
+  # Temperature offset:
+  # A calibration from -7 to +3 for the temperature sensor of the BMP280
+  - platform: template
+    name: "Temperature Offset"
+    id: temperature_offset_setter
+    min_value: -7
+    max_value: 3
+    step: 0.1
+    lambda: |-
+      return id(temperature_offset);
+    set_action:
+      then:
+        - globals.set:
+            id: temperature_offset
+            value: !lambda 'return float(x);'
+