added ros2 publishers section

Author: Tomas Baca

docs/10-prerequisites/25-ros2/50-ros1-ros2-patterns/51-publishers.md

@@ -0,0 +1,29 @@
+---
+title: Publishers
+pagination_label: Publishers
+description: ROS2 Publishers
+---
+
+# ROS2 Publishers
+
+## Creating a latched publisher
+
+Latching can be enabled through QoS.
+
+1. Setup a QoS profile using a baseline of your choice.
+```cpp
+rclcpp::QoS qos_profile = rclcpp::SystemDefaultsQoS();
+```
+2. Enable the `transient_local()` durability setting:
+```cpp
+qos_profile.transient_local();
+```
+1. Pass the QoS profile to the publisher handler using the `PublisherHandlerOptions`:
+```cpp
+mrs_lib::PublisherHandlerOptions ph_options;
+
+ph_options.node = node_;
+ph_options.qos = qos_profile;
+
+ph_my_topic_ = mrs_lib::PublisherHandler<my_type>(ph_options, "~/topic_out");
+```