Updated docuemntation and launch files

README.md

 ## Description
 
-The iri_laser_scan_icp project description
+This node provides a service server to process an ICP between two scans using [laser_scan_utils](https://gitlab.iri.upc.edu/labrobotica/algorithms/laser_scan_utils).
+
+This node also provides the following configuration files located in [config](./config) directory:
+  * **params.yaml**: Node default configuration file.
 
 # ROS Interface
-### Service clients
-  - ~**icp** (iri_laser_scan_icp/icp.srv)
 ### Service servers
-  - ~**icp** (iri_laser_scan_icp/icp.srv)
+  - ~**icp** (iri_laser_scan_icp/icp.srv): Performs an ICP.
 
 ### Parameters
 - ~**rate** (Double; default: 10.0; min: 0.1; max: 1000) The main node thread loop rate in Hz. 
+- ~**range_std_dev** (Double; default: 0.035; min: 0.01; max: 0.1) Standard deviation measurement noise in range in meters. 
+- ~**angle_std_dev** (Double; default: 0.05; min: 0.01; max: 0.2) Standard deviation measurement noise in angle in radians. 
 
 ## Installation
 
+#### IRI dependencies
+
+* **laser_scan_utils**: This is a C++ Toolbox with utilities for 2D laser scan processing. Follow the instructions on the [repository](https://gitlab.iri.upc.edu/labrobotica/algorithms/laser_scan_utils) README to install the library with all the optional dependencies.
+
+#### External dependencies
+
+* **[Eigen](https://eigen.tuxfamily.org/index.php?title=Main_Page)**: Follow its installation instructions.
+
+#### Other dependencies
+
 Move to the active workspace:
 ```bash
 roscd && cd ../src
@@ -34,9 +47,20 @@ catkin_make
 
 ## How to use it
 
-- Standalone test
+This node provides the following launch files:
+
+- **node.launch**: Launch file intended to be included by a general launch file. It has the following arguments:
+  - *node_name*: Node name.
+  - *config_file*: Node configuration yaml file.
+  - *icp_service_name*: Laser scan ICP to be remaped.
+  - *output*: Ros node launch output's parameter.
+  - *launch_prefix*: Ros node launch launch-prefix's parameter.
 
-  `roslaunch iri_laser_scan_icp test.launch`
+- **test.launch**: Launch file for development purpouses. It has the following arguments:
+  - *output*: Ros node launch output's parameter.
+  - *launch_prefix*: Ros node launch launch-prefix's parameter.
+  - *dr*: Boolean to launch rqt_reconfigure.
+  - *sim_time*: Boolean to set */use_sim_time* parameter.
 
 ## Disclaimer  
 

launch/test.launch

@@ -5,6 +5,9 @@
   <arg name="launch_prefix" default=""/>
   <arg name="dr"            default="true"/>
 
+  <arg name="sim_time"      default="false"/>
+  <param name="/use_sim_time" value="$(arg sim_time)" />
+
   <include file="$(find iri_laser_scan_icp)/launch/node.launch">
     <arg name="node_name"     value="iri_laser_scan_icp"/>
     <arg name="output"        value="$(arg output)"/>