doc: netconf-tests: add Tutorial into README

Add description for new users, including references to NETCONF and Yang.
Basic examples - get-config and edit-config.

Related to #14

Author: cejkato2

netconf-tests/README.md

@@ -1,10 +1,77 @@
+This file contains brief tutorial for new users. The second section describes
+testing environment and test cases prepared for the OF-CONFIG server (OFC).
+
+Tutorial
+========
+
+After successful installation described in [INSTALL.md](../INSTALL.md)
+OFC can be started using:
+
+```
+$ ofc-server
+```
+
+OFC starts automatically in the daemon mode (in the background).
+Passing -f starts OFC in the foreground.
+
+OFC can be used to configure running Open vSwitch (OVS). Therefore, OVS should
+be running as well (it is recommended to start OVS before OFC). OFC modifies
+OVSDB that means it is **NOT** recommended to modify OVSDB by external tools.
+
+The OF-CONFIG protocol that is implemented by OFC comes from the NETCONF
+protocol specified by [RFC6241](http://tools.ietf.org/html/rfc6241). The RFC
+document describes the protocol in detail. It contains various examples for
+users' inspiration.
+
+Data that should be send to OFC is in the XML format. It must be formed
+according to rules specified by configuration data model
+[of-config.yang](../model/of-config.yang). The data model is written in the
+Yang language specified by [RFC6020](http://tools.ietf.org/html/rfc6020).
+
+To communicate with OFC, any NETCONF or OF-CONFIG client application must be
+used. Some examples of NETCONF clients
+([netopeer-cli](https://code.google.com/p/netopeer) and
+[Netopeer-GUI](https://github.com/CESNET/Netopeer-GUI)) are
+referenced in [../INSTALL.md](../INSTALL.md).
+
+XML files contained in this directory can be used to understand how to apply
+information from RFC6241 and RFC6020 on OFC. Bash scripts from this directory
+execute a NETCONF client called netopeer-cli that connects to OFC and
+communicates with it. netopeer-cli allows us to get or modify OVS configuration
+and state data.
+
+To get content of the current "running" configuration use:
+
+```
+$ netopeer-cli
+netconf> connect --login username address
+.... prompt for password if required by the remote host ...
+netconf> get-config running
+.... probably long output with data ...
+```
+
+This is what the [get-config.sh](./get-config.sh) script does...
+(Note: we use filter in the script to get only OVS related data)
+
+To modify running configuration, there is edit-config command. When we execute:
+
+```
+netconf> edit-config running
+```
+
+We will be asked for configuration data (in XML) formed with respect to data
+model. Valid data is sent to OFC and configuration changes.
+
+There is a lot of examples of XML files for modification of configuration of
+OVS.
+
 Testing OF-CONFIG functionality
 ===============================
 
 Testing environment
 -------------------
 
-Test scripts work with installed netopeer-cli. Netopeer-cli comes from [Netopeer package](https://code.google.com/p/netopeer).
+Test scripts work with installed netopeer-cli.
 
 Scripts connect to localhost as current user.
 It is required to have working public-key authentication
@@ -16,7 +83,7 @@ See 'config' file and edit credentials to login into OF-CONFIG server.
 SSH server should be added into known hosts before running tests. Connect to the server
 using netopeer-cli with the same username and approve server's fingerprint.
 
-Warning: this setting is highly insecure and MUST NOT be used in production environment.
+Warning: this setting is highly insecure and **MUST NOT** be used in production environment.
 For testing purposes, empty password or private key without passphrase allows scripts
 to be non-interactive.