This was lost in commit 8ead8f7e, because this was never implemented
for the new API.

Allow the compiler to invalidate buffer contents.

Manages memory automatically.

The implicit cast operator can be very dangerous.

Fixes build failure because Bionic doesn't provide SUN_LEN().

For improved portability of the net library to projects without
autoconf.

Not used anymore.

There is not much use in GLib: on Windows, we have a native API for
string collation, and the rest uses either libicu or the standard C
library calls.

We don't need this anymore: Win32 doesn't use this library at all, and
everything else has either iconv() or libicu.

default_value defaults to nullptr.

Since we are removing GLib, this call is useless.

I suppose there is no non-WIN32 operating system that doesn't have
fnmatch().  So let's remove the GLib implementation.

Drop support for misencoded tags.  People should not be using ID3v1
anyway.