... in order to make standard containers be able to store it. Required for
#5532 (#4899) and the recording PR.
This includes:
* removing the `LocklessRingBuffer<sampleFrame>` specialization
* passing samplerame in `StereoDelay::tick` as a reference
Additional cleanups:
* removing already unused typedef `sampleFrameA`
* add some `const_cast` to make code more readable
* advanced config: expose hidden constants to user screen
* advanced config: add support for FFT window overlapping
* waterfall: display at native resolution on high-DPI screens
* waterfall: add cursor and improve label density
* FFT: fix normalization so that 0 dBFS matches full-scale sinewave
* FFT: decouple data acquisition from processing and display
* FFT: separate lock for reallocation (to avoid some needless waiting)
* moved ranges and other constants to a separate file
* debug: better performance measurements
* minor fixes
* build the ringbuffer library as part of LMMS core
