Update README.md: add system requirements and fix rosdep call

README.md

@@ -20,6 +20,7 @@ instructions further below in this document. Please note that the setup uses vnc
 
 - Ubuntu 18.4
 - ROS Melodic
+  - *additionally required packages:* `ros-melodic-libfranka` `python-catkin-tools` `libeigen3-dev`
 
 ## Installation
 
@@ -37,7 +38,7 @@ instructions further below in this document. Please note that the setup uses vnc
         - `git clone https://git-st.inf.tu-dresden.de/ceti/ros/panda_simulation.git` **or** `git clone git@git-st.inf.tu-dresden.de:ceti/ros/panda_simulation.git`
         - `git clone https://git-st.inf.tu-dresden.de/ceti/ros/sample_applications.git` **or** `git clone git@git-st.inf.tu-dresden.de:ceti/ros/sample_applications.git`
         - change into the workspace main directory `cd ..`
-- install ROS package dependencies `rosdep install --from-paths .`
+- install ROS package dependencies `rosdep install -i --from-paths .`
 - build the workspace `catkin build`
 - source the config: depending on your shell
     - `source devel/setup.bash` (default)