Psifr: Analysis and visualization of free recall data

This version fixes a problem with the count_unique option in the distance CRP analysis. It also adds support for counting non-unique lags, which will be necessary for implementing a block CRP analysis.

• Using the count_unique option for psifr.fr.distance_crp will now only increment each distance bin as possible once per transition. Previously each unique possible distance value was recorded for each transition, rather than each unique possible distance bin.
• A count_unique option has been added to psifr.transitions.count_lags to handle cases where multiple possible transitions may have the same lag.
• A configuration file for Zenodo has been added to set project information automatically.