COMMON: Add hash.h to the noinst_HEADERS
AURORA: Add new types in Dragon Age II
AURORA: Add missing include
COMMON: For portability, use generic_string() instead of string()

Thanks to darkstar.
COMMON: Replace MKID_BE by MKTAG

MKID_BE relied on unspecified behavior of the C++ compiler,
and as such was always a bit unsafe. The new MKTAG macro
is slightly less elegant, but does no longer depend on the
behavior of the compiler.
Inspired by FFmpeg via ScummVM.
SOUND: Add MP3 detection

We determine that a stream is a MP3 stream if
a) We find an ID3v2 tag   or
b) We find a sane MPEG frame header

This is not fool proof, but should suffice for us.
Should false positives become a problem later one, we should
a) Calculate frame lengths and check next $n frames   and
b) Check the ID3v2 tag for sanity   and
c) Also check for sane frame headers when we found an ID3v2 tag