Create install_kdl.md

For roboticslab-uc3m/questions-and-answers#5 (comment)

install_kdl.md

@@ -0,0 +1,14 @@
+## Install KDL (Ubuntu 14.10)
+
+We use KDL for kinematics. Official download page: [link](http://www.orocos.org/kdl). </br>
+Installing KDL on Ubuntu is quite straightforward. Note that you will be prompted for your password upon using '''sudo''' a couple of times:
+
+```bash
+sudo apt-get install libeigen3-dev
+cd  # go home
+mkdir -p repos; cd repos  # make $HOME/repos if it doesn't exist; then, enter it
+git clone https://github.com/orocos/orocos_kinematics_dynamics.git
+cd orocos_kinematics_dynamics/orocos_kdl; mkdir build; cd build
+cmake ..
+make -j3;  sudo make install; sudo ldconfig; cd  # go home
+```