Update roadmap for the rest of the year (#431)

Signed-off-by: Addisu Z. Taddese <addisu@openrobotics.org>

Author: azeey

roadmap.md

@@ -21,6 +21,31 @@ info@openrobotics.org.
 * **Define platform dependencies and prepare for the new Ubuntu LTS 24.04 and the interaction with ROS 2 Jazzy.**
 * **Support nested models in Bullet-featherstone gz-physics engine plugin**
 
+## 2024 Q1 (Jan - Mar)
+
+* **Improve documentation website (gazebosim.org/docs)** (Continued from Q4/2023)
+* **Migrate from Qt5 to Qt6** (https://github.com/gazebosim/gz-gui/issues/586) (Continued from Q4/2023)
+* **Define platform dependencies and prepare for the new Ubuntu LTS 24.04 and the interaction with ROS 2 Jazzy.** (Continued from Q4/2023)
+* **Support nested models in Bullet-featherstone gz-physics engine plugin** (Continued from Q4/2023)
+* **Align ROS and Gazebo messages where possible**
+  * Make performance improvements to the `ros_gz` bridge
+* **Improve performance of Rendering Sensors (e.g., Lidar, Depth Cameras)**
+* **Set state of simulation in SDFormat (e.g. initial joint position and velocity)**
+
+## 2024 Q2 (Apr - Jun)
+
+* **Migrate from Qt5 to Qt6** (https://github.com/gazebosim/gz-gui/issues/586) (Continued from Q1/2024)
+* **Complete Bullet-featherstone implementation**
+* **Improve performance of Rendering Sensors (e.g., Lidar, Depth Cameras)** (Continued from Q1/2024)
+* **Create a third party plugin repository**
+
+## 2024 Q3 (July - Sep)
+
+* **Create a third party plugin repository** (Continued from Q2/2024)
+* **Implement Mimic joints for DART**
+* **Prepare for release (feature freeze/code freeze)**
+* **Prepare and Run tutorial party**
+
 ## Feature Roadmap
 
 A number of features are planned for specific releases of Gazebo. The