Added (excluded) Dropzone Module for more comprehensive module example (#4098)

* DropzoneModule hello world

* Buttoning things up

* Exclude by default

* Upstream refs

* Cleanup

* Add modules folder to path

* Case and path matters

* Exclude from header

* Guard

src/modules/DropzoneModule.h

@@ -0,0 +1,37 @@
+#pragma once
+#if !MESHTASTIC_EXCLUDE_DROPZONE
+#include "SinglePortModule.h"
+#include "modules/Telemetry/Sensor/DFRobotLarkSensor.h"
+
+/**
+ * An example module that replies to a message with the current conditions
+ * and status at the dropzone when it receives a text message mentioning it's name followed by "conditions"
+ */
+class DropzoneModule : public SinglePortModule, private concurrency::OSThread
+{
+    DFRobotLarkSensor sensor;
+
+  public:
+    /** Constructor
+     * name is for debugging output
+     */
+    DropzoneModule() : SinglePortModule("dropzone", meshtastic_PortNum_TEXT_MESSAGE_APP), concurrency::OSThread("DropzoneModule")
+    {
+        // Set up the analog pin for reading the dropzone status
+        pinMode(PIN_A1, INPUT);
+    }
+
+    virtual int32_t runOnce() override;
+
+  protected:
+    /** Called to handle a particular incoming message
+     */
+    virtual ProcessMessage handleReceived(const meshtastic_MeshPacket &mp) override;
+
+  private:
+    meshtastic_MeshPacket *sendConditions();
+    uint32_t startSendConditions = 0;
+};
+
+extern DropzoneModule *dropzoneModule;
+#endif