Do we still need Buffer:atSec and Buffer:atPair?

[esluyter]

in extSuperPair.sc:

+ Buffer {
    atSec { arg secs;
        ^SuperPair.fromDouble(min(secs * sampleRate, numFrames));
    }
    atPair { arg a, b;
        ^SuperPair(a, b).asFloat / sampleRate;
    }
}