Added Charlie Kaufman's SECDIR review comments:

Typos:
 Page 5: 'build-in' -> 'built-in'
 Page 17: 'causes no hard' -> 'causes no harm'

Corrected multiple occasions where, e.g. 'RFC 5095' was used instead of [RFC5095].

From Alexey Melnikov's Gen-ART review comments:

In 1.1

This document complements the IPv6 node requirements [RFC6434] in
  places where clarifications are needed the with discussion on the use

Deleted 'the' before 'with'.

Signed-off-by: Jouni Korhonen <jouni.korhonen@renesasmobile.com>