Don't use global variables.

Decouple command/OtherCommands.cxx from the "simple" database plugin.

Don't depend on the "simple" database plugin.  This fixes an assertion
failure / crash and allows using stickers with other plugins.

Make it "const".

sed gone horribly wrong.  D'oh!

pthread_setname_np() doesn't have the "thread" argument on OS X.

Fixes non-Linux build without neighbor plugins.

Another big chunk of code for multi-player support.

The pkg-config file has been added in Samba 4.0.  This commits adds a
fallback for older libsmbclient versions.

Allow semicolons and single quotes in the stream title.  This is not
part of any specification, but found in real life.

We're C++, and sparse understands only plain C.

Was broken on out-of-tree builds.

This was just too complex and fragile.  Anybody who has versioned
program names shall just call those programs manually.

I expect that aclocal is clever enough to find its own include
directories.  If it does not, letting MPD guess it is not the most
reliable idea either.