Replace custom insertion_model by serializers

backend/dev_data/IGC_sample.annotation_OF.summary

...agenedb/apps/catalog/migrations/0003_complete_taxonomy.py

...edb/apps/catalog/migrations/0004_taxonomy_superkingdom.py

.../metagenedb/apps/catalog/migrations/0005_gene_ordering.py

backend/metagenedb/apps/catalog/models/gene.py

backend/metagenedb/apps/catalog/views/gene.py

backend/metagenedb/apps/catalog/views/insertion_model.py

backend/scripts/populate_db/import_igc_data.py

backend/scripts/populate_db/test_import_igc_data.py