Add configs for WOFF 2.0 font files (`.woff2`)

* Serve `.woff2` files with far-future expires headers and with
  the current specification suggested media type, namely
  `application/font-woff2` (note: this media type is not yet
  registered with IANA, however, things aren't likely to change).

* Ensure that `.woff2` files aren't served with any of the `HTML`
  document related headers, and they are accessible even cross-domain.

Node: There is no need to compress WOFF 2.0 fonts as they are already
compressed!

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Huge thanks to Vladimir Levantovsky for all his help!

Ref: http://www.w3.org/TR/WOFF2/
     h5bp/server-configs-apache#32

Close h5bp/server-configs-apache#32