Add custom component example to rosbot_description

Author: rafal-gorecki

rosbot_description/config/rosbot/custom.yaml

@@ -1,2 +1,16 @@
 ---
+# Put your own components here. `type: custom` attaches a user-supplied
+# URDF/xacro + mesh. Template + docs:
+# https://github.com/husarion/husarion_components_description#custom-component
+#
+# Example (uncomment to spawn the shipped template, e.g. `... simulation.yaml
+# robot_model:=rosbot configuration:=custom`):
+#
+#   - type: custom
+#     package: husarion_components_description
+#     file: urdf/custom_component_example.urdf.xacro
+#     name: my_marker
+#     parent_link: cover_link
+#     xyz: 0.0 0.0 0.1
+#     rpy: 0.0 0.0 0.0
 components: []