Create GPIOControl.h for GPIO control module interface

Author: awhite2000

src/GPIOControl.h

@@ -0,0 +1,20 @@
+# GPIO Control Module Interface
+
+This header file defines the interface for controlling GPIO pins through mesh messages.
+
+## Functions
+
+### void gpio_init();
+- Initializes the GPIO pins.
+
+### void gpio_set_pin(int pin, bool value);
+- Sets the specified GPIO pin to the given value.
+
+### bool gpio_get_pin(int pin);
+- Returns the current value of the specified GPIO pin.
+
+### void gpio_toggle_pin(int pin);
+- Toggles the value of the specified GPIO pin.
+
+### void gpio_send_mesh_message(MeshMessage message);
+- Sends a mesh message to control GPIO pins.