docs: Fix power module docs

Signed-off-by: Rahix <rahix@rahix.de>

Documentation/index.rst

@@ -31,6 +31,7 @@ Last but not least, if you want to start hacking the lower-level firmware, the
    pycardium/light-sensor
    pycardium/os
    pycardium/personal_state
+   pycardium/power
    pycardium/simple_menu
    pycardium/utime
    pycardium/vibra

Documentation/pycardium/power.rst

-.. py:module:: Power
+.. py:module:: power
 
 ``power`` - PMIC power module handling
 ======================================
+.. versionadded:: 1.4
+
 The :py:mod:`power` module allows you to read the card10's power status
 in your scripts.
 
@@ -22,22 +24,32 @@ in your scripts.
 
       Card10 will hard-shutdown once the voltage drops below 3.4 V
 
+   .. versionadded:: 1.4
+
 .. py:function:: read_battery_current()
 
    Read the battery-side current flow in A.
 
+   .. versionadded:: 1.4
+
 .. py:function:: read_chargin_voltage()
 
    Read the charge voltage in V.
 
+   .. versionadded:: 1.4
+
 .. py:function:: read_chargin_current()
 
    Read the charge current in A.
 
+   .. versionadded:: 1.4
+
 .. py:function:: read_system_voltage()
 
    Read the system-side voltate in V.
 
+   .. versionadded:: 1.4
+
 .. py:function:: read_thermistor_voltage()
 
    Read the thermistor voltage in V.
@@ -45,3 +57,5 @@ in your scripts.
    There is a resistor network from GND over a thermistor
    (10K at room temperature) over 10K to the Thermistor Bias voltage.
    This reads the voltage between thermistor and resistor.
+
+   .. versionadded:: 1.4