Add SQLite build script for OSX.
Add DISABLE_FFAST_MATH flag to environment.sh (used by build_sqlite.sh).
Add $MIXXX_LIB/include to include path and $MIXXX_LIB/lib to lib path in environment.sh.
Don't build Qt SQLite plugin and link to an external SQLite library when
building Qt4.
Fix some typos in SETUP details.
Fix chromaprint install name.
Add opus and opusfile build script.
Build opus/opusfile and SQLite.