* Speed up spectrogram painting by releasing mutex in FFTDataServer while calculating data prior to writing it, and by adding whole-column value query methods to FFT objects * Add paint cache to Thumbwheel -- repaints of this widget were slowing down the whole spectrogram repaint * More uses of MutexLocker (named and with debug) and more profile points * Make startup much quicker some of the time, with OSC server in place