Remove old submodule BEETL.
Add fixed version of BEETL as submodule.
Let the prefix manager to be able to handle gzip-ed files through BGZF (currently it is really slow!).
Add all the reads to the prefix manager so that the lexicographic order of the reads is reconstructed.
Merge branch 'master' of github.com:AlgoLab/LightStringGraph
Do not open the prefix-file until the first push is made.
Fix debug messages during basic arc interval construction.