v1.6 - 2012-04-13 - TCP SYN ping
---------------------------------
 - Changed TCP ping method, from ACK to SYN;
 - Recognizing more ping format strings;


v1.5 - 2012-03-21 - DNS for IPv6
---------------------------------
 - Added DNS address resolution for IPv6 (i.e. 'AAAA' resource records);
 - Added support for more than one protocol per host;
 - Many code improvements;


v1.4 - 2012-03-14 - Network Interface per host
---------------------------------
 - Each host may define its own source network interface, or it can use a
   global network interface;


v1.3 - 2012-02-21 - Test cases
---------------------------------
 - Test cases for the major classes;
 - Refactor of configuration classes;
 - Possibility to change the log level on-the-fly;
 - Many fixes resulting from test cases;


v1.2 - 2011-12-11 - IPv6 ping
---------------------------------
 - ICMPv6 ping;
 - TCP ping over IPv6;


v1.1 - 2011-08-26 - TCP ping
---------------------------------
 - TCP ping throught ACK/RST segments at configurable transport layer port;
 - Improvement of MessagePayload class with append(), also a 32 bits versions of
   encode() and decode() methods;


v1.0 - 2011-07-30 - ICMP ping
---------------------------------
 - Released the first version of pingcheck with support to a basic ICMP ping
   through Echo Request, Echo Reply and Destination Unreachable packets;
 - DNS resolver for IPv4 addresses through Andreas Haberstroh's Boost DNS
   library;
 - Caching of DNS resolved addresses until its time-to-live expires, which will
   cause another query;
 - The list of host to ping can be provided by a configuration file or by
   command line;
 - Using libi2ncommon for logging services;