Defining our own types for IP Addresses

[gabhijit]

We already have types for Ethernet MAC Address (MACAddress) and Ether Type (EtherType) defined which work well for us for Debug and Display printing and any other custom handling. Along the similar lines, we should be defining -

1. IPv4 and IPv6 address types.
2. IP Options types for different IP options

[gabhijit]

This commit completes basic implementation of IPv4 and IPv6 address types.