ported rtabmap_ros_pkg_split to ros2

rtabmap_msgs/msg/UserData.msg

@@ -0,0 +1,12 @@
+
+std_msgs/Header header
+
+# OpenCV matrix containing the user data. A matrix of type CV_8UC1 
+# with 1 row is considered to be compressed (with rtabmap::compressData() method).
+# If you have one dimension unsigned 8 bits uncompressed data, make sure to transpose it
+# (to have multiple rows instead of multiple columns) in order to be detected as
+# not compressed.
+uint32 rows
+uint32 cols
+uint32 type
+uint8[] data