Old suffix_tree dependance

[sergiigladchuk]

Hi. I perform analysis of big set of RNA-seq data from cancers, and wanted to check out this IG repertoar direction as well. I usually run all analysis in snakemake and install all dependencies from conda (conda-forge and bioconda channels). If there are interesting results, it is very easy to reproduce them in such an environment. So in order to run your program I installed all the dependencies except suffix_tree, which appears to be very old implementation with no license. Most probably it will not be added to conda-forge, since they are going to move to Python 3 completely in a year. So maybe usage of other newer implementation of suffix trees from pupi.org would be more appropriate. Also it is good notion for you to switch imrep to Python 3 completely, so it is more attractive for analysis in the future.