Added Spike2 classifications option

I think. Maybe.
Fixed a bug with alignment times

Replaceecodes.m looks for a pair of triggers that are x seconds apart,
where x is the length of the first good trial, and aligns spike2 trigger
times and rex times to that. However, if this fails, it now defaults to
aligning the first trigger with the first rex trial start time. This
might not always yield correct alignments.
Updated the README
Minor tweak
progress on Spike2 file processing

still debugging to do
new file name convention
re-set Radu's minor tweak
Implemented cross correlation for time align
remove end trigs for better correlation
prevent issue when reprocessing (reproc)
added calculation of average error
cleaned up and added some changes from Radu
some housekeeping

debugging small errors along the way