added tests for get_all_Genes_by_source, is_chromosome, has_karyotype, karyotype_rank and forced expand methods
added tests for get_all_Genes_by_source, is_chromosome, has_karyotype, karyotype_rank and forced expand methods

danstaines/ensembl,muffato/ensembl,Ensembl/ensembl,danstaines/ensembl,james-monkeyshines/ensembl,Ensembl/ensembl,at7/ensembl,james-monkeyshines/ensembl,at7/ensembl,mjg17/ensembl,muffato/ensembl,mjg17/ensembl,james-monkeyshines/ensembl,Ensembl/ensembl,at7/ensembl,muffato/ensembl,Ensembl/ensembl,james-monkeyshines/ensembl,danstaines/ensembl,at7/ensembl,mjg17/ensembl,mjg17/ensembl,muffato/ensembl