Rewrote selectROIs as class. Update to pxCov and binMov.

The selectROIs GUI was completely re-written. Changes to functionality
are minimal, but the code is very different. Two changes affect
compatibility: selectROIs now requires a binary movie file (evaluating
traces is necessary for judging ROIs). selectROIs also now requires the
pixel covariances to be calculated with the function written by Matthias
(calcPxCovMJLM, but to be renamed to calcPcCov).
Updated calcPxCov algo. UPDATE YOUR INIT FUNS!

The default pixel covariance method is now the version originally
written by Matthias. This must be used for the new selectROIs GUI. The
input parameters have changed (no more "seedBin"), so you need to update
your processing pipelines. calcSeedCov and Selmaan's experimental
calcPxCov were renamed to *Old.