Don't ignore unsynchronisation flags in ID3v2 tag and frame headers

[Scott Wheeler]

Lukáš Lalinský wrote:
> Hi,
>
> this is an updated bug fix for
> http://bugs.kde.org/show_bug.cgi?id=138829 - I still feel unsure about
> what am I allowed to commit to SVN and what not, and since this is an
> API change, it's probably better to have it reviewed before
> committing...
>   

Specifically it's a binary / source incompatible API change, which
shouldn't go in as it is.  The only problem that I see at the moment is
to the createFrame method.  The old version needs to be supported, even
if it is marked as deprecated.  TagLib is still binary compatible back
to TagLib 1.0.

If you leave the old one in place though, I'm fine with this being
checked in.

-Scott