Version 0.8.8: added "user_data" field in database. Added WifiMapping example. Fixed FATAL error when initializing rtabmap with no database.

examples/WifiMapping/CMakeLists.txt

@@ -0,0 +1,33 @@
+
+SET(INCLUDE_DIRS
+	${PROJECT_SOURCE_DIR}/utilite/include
+	${PROJECT_SOURCE_DIR}/corelib/include
+	${PROJECT_SOURCE_DIR}/guilib/include
+    ${OpenCV_INCLUDE_DIRS}
+    ${PCL_INCLUDE_DIRS}
+)
+
+IF("${RTABMAP_QT_VERSION}" STREQUAL "4")
+    INCLUDE(${QT_USE_FILE})
+ENDIF()
+
+SET(LIBRARIES
+	${OpenCV_LIBRARIES}
+	${QT_LIBRARIES} 
+	${PCL_LIBRARIES}
+)
+
+INCLUDE_DIRECTORIES(${INCLUDE_DIRS})
+
+IF("${RTABMAP_QT_VERSION}" STREQUAL "4")
+    QT4_WRAP_CPP(moc_srcs ../RGBDMapping/MapBuilder.h MapBuilderWifi.h)
+ELSE()
+    QT5_WRAP_CPP(moc_srcs ../RGBDMapping/MapBuilder.h MapBuilderWifi.h)
+ENDIF()
+
+ADD_EXECUTABLE(wifi_mapping main.cpp ${moc_srcs})
+  
+TARGET_LINK_LIBRARIES(wifi_mapping rtabmap_core rtabmap_gui rtabmap_utilite ${LIBRARIES})
+
+SET_TARGET_PROPERTIES( wifi_mapping 
+  PROPERTIES OUTPUT_NAME ${PROJECT_PREFIX}-wifi_mapping)