* Add correct mp3lame configure check since it does not use pkg-config
* Update mod_shout Makefile to log failure message if mp3lame not available
* Rewrite #include for lame.h to lame/lame.h in mod_shout.c
* Explicitly define dependency tree for several modules
* Enable parallel builds for libtiff and libspandsp
* Verify module is enabled before attempting build. Allows
the virtual targets to be used for ordering without forcing
a build dependency.