conexus 0.2.1 released

This release has some cleanup and some new features. The autoconf check for std::tr1::array has been removed since it is no longer used. This should make it easier to build with compilers that do not have tr1 yet.

The IP address classes including IPv4::Address and IPv6::Address now have typedefs and create() methods to support smart pointer creation. IPv6::Address now has a constructor that can take an IPv4::Address as a parameter, and IPv4::Address has a similar constructor that checks whether the IPv6 address is IPv4 compatible.

Finally, dependency on pcap and building the PacketCapture classes are now optional in autoconf.