* Better handling of libexecinfo. I moved from adding some goo to
CMakeLists.txt to writing proper FindExecinfo.cmake package.
* Force source directory, or visualization presets could miss
installation;
* Force "plist" in WANTLIB, as it's being used by plugin;
* Add back fftw3 dependency: while we use external libchromaprint now,
fftw3 is also needed for so called "moodbar".
* Nit: remove libnjb, it's use was actually gone in the last release;
Lots of input from sthen@ and nigel@, committing ASAP.