Plane: compiler warnings

- float to double in gcs_send_test (x2)
- float to bool

ArduPlane/GCS_Mavlink.cpp

@@ -1356,16 +1356,16 @@ void GCS_MAVLINK::handleMessage(mavlink_message_t* msg)
                 plane.home_is_set = HOME_SET_NOT_LOCKED;
                 result = MAV_RESULT_ACCEPTED;
                 plane.gcs_send_text_fmt(PSTR("set home to %.6f %.6f at %um"),
-                                        new_home_loc.lat*1.0e-7f,
-                                        new_home_loc.lng*1.0e-7f,
-                                        (unsigned)(new_home_loc.alt*0.01f));
+                                        (double)(new_home_loc.lat*1.0e-7f),
+                                        (double)(new_home_loc.lng*1.0e-7f),
+                                        (uint32_t)(new_home_loc.alt*0.01f));
             }
             break;
         }
 
         case MAV_CMD_DO_AUTOTUNE_ENABLE:
             // param1 : enable/disable
-            plane.autotune_enable(packet.param1);
+            plane.autotune_enable(!is_zero(packet.param1));
             break;
 
         default:

ArduPlane/commands_logic.cpp

@@ -662,7 +662,7 @@ bool Plane::verify_altitude_wait(const AP_Mission::Mission_Command &cmd)
         return true;
     }
     if (auto_state.sink_rate > cmd.content.altitude_wait.descent_rate) {
-        gcs_send_text_fmt(PSTR("Reached descent rate %.1f m/s"), auto_state.sink_rate);
+        gcs_send_text_fmt(PSTR("Reached descent rate %.1f m/s"), (double)auto_state.sink_rate);
         return true;        
     }