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* Change of contact mail to academic adresses
* Function of bitarray_ph4 library replaced by new versioof equivalents in bitarray library
* Bug in the argument "-last" is fixed. Now it defaults to None instead of -1
* New argument "-max_clust" lets user specify the maximum number of cluster to calculate
* New argument "-numouts" lets users specify a number of clusters and leaders to be printed as independent pdb files
* The function "load_trajectory" now raise errors if selections are incorrect or contain no atoms
* The function "load_trajectory" now treat selections in a way that improve RAM savings