Merge release 4.2.0 into pantools_v4

• Added variation functions add_variants, add_pavs,remove_variants, remove_pavs and variation_overview
• VCF information can be used for msa, core_phylogeny and consensus_tree
• PAV information can be used for gene_classification, pangenome_structure, msa, core_phylogeny and consensus_tree
• add_annotations now validates all data before adding it to the graph
• msa can provide output data for all phenotypes instead of just one.