Added update for issue #122
Added Latex PDF for issue #122 and fixes
Minor changes to Latex PDF for issue #122 and fixes
Make msm_acf variable names consistent with PDF
Added note about subtracting the mean
In msm_acf tests, calculate ACF to longer lagtimes.  Also pep8 fixes.
Merge pull request #124 from SimTk/acf_fix

Acf fix merged.  closes issue #122