There's just one caller, i.e. ScanGenericTags(), which is documented
to throw exceptions.

Map ID3 "TIT1" to this new core tag type.

Closes https://github.com/MusicPlayerDaemon/MPD/issues/563

Since we switched from autotools to Meson in commit
94592c14, we don't need to include
`config.h` early to properly enable large file support.  Meson passes
the required macros on the compiler command line instead of defining
them in `config.h`.

This means we can include `config.h` at any time, whenever we want to
check its macros, and there are no ordering constraints.

Replaces GLib's GError.

Remove GLib dependency from some headers.

Use _scan() instead, to have more control.

Pass a callback table to scan_file() and scan_stream(), instead of
returning a tag object.

After we've been hit by Large File Support problems several times in
the past week (which only occur on 32 bit platforms, which I don't
have), this is yet another attempt to fix the issue.