added ci support

.gitlab-ci.yml

+variables:
+  GIT_SUBMODULE_STRATEGY: recursive
+  GIT_CLONE_PATH: $CI_BUILDS_DIR
+
+stages:
+  - build
+
+build-ws:
+  image: ros:melodic-ros-base-bionic
+  stage: build
+  script:
+    - apt-get update
+    - apt-get install -y ros-melodic-libfranka python-catkin-tools libeigen3-dev 
+    - apt-get install -y build-essential
+    - apt-get install -y gcc
+    - apt-get install -y make
+    - apt-get install -y cmake
+    - apt-get install -y libssl-dev
+    - echo "source /opt/ros/melodic/setup.bash" >> ~/.bashrc
+    - source ~/.bashrc
+    - rosdep install -y --from-paths .
+    - git clone https://github.com/eclipse/paho.mqtt.c.git
+    - cd paho.mqtt.c
+    - git checkout v1.3.1
+    - cmake -Bbuild -H. -DPAHO_WITH_SSL=ON -DPAHO_ENABLE_TESTING=OFF
+    - cmake --build build/ --target install
+    - ldconfig
+    - cd ..
+    - git clone https://github.com/eclipse/paho.mqtt.cpp
+    - cd paho.mqtt.cpp
+    - cmake -Bbuild -H. -DPAHO_BUILD_DOCUMENTATION=FALSE -DPAHO_BUILD_SAMPLES=FALSE -DPAHO_BUILD_SAMPLES=FALSE
+    - cmake --build build/ --target install
+    - ldconfig
+    - catkin build