This patch adds support for a few of new C++11 features. I added only the
ones easy to implement (basically, just adding keywords to lists), since
I'm not familiar with the way cc-mode works. Hope this patch is not
controversial. I submitted required legal papers years ago, you can find a
few my patches in ChangeLog.

Paul


2014-01-25  Paul Pogonyshev  <pogonyshev@gmail.com>

    * progmodes/cc-langs.el: Support some of the new keywords in
    C++11.
    (c-operators): Handle `alignof' and `decltype'.
    (c-primitive-type-kwds): Add `char16_t' and `char32_t' primitive
    types.
    (c-type-modifier-kwds): Add `constexpr' and `thread_local'.
    (c-constant-kwds): Add `nullptr'.