Various build-dep bumps
Correlate: Avoid re-reading data unless necessary
PackedVec: Add instances
PackedVec: Add sum
PackedVec: Refactor functions on streams
Move tests to hphoton-correlate
SparseCorr.rebin: Fix fix bin

Forgot to round to nearest bin
correlate: Move logCorr into SparseCorr
SparseCorr: Force INLINE of corr
SparseCorr: Error checking
SparseCorr: Slightly improve error handling
Add correlation function description
Add doc/Makefile
Fix a few typos