Import Mapview transcript mappings for ALT_REF_LOCI contigs
For both hg19 and hg38 we have the ALT_REF_LOCI contigs defined as chromosomes in our database (see !20 (closed)), but we ignore their mappings in the Mapview file on import, making them useless.
Leaving the issue of other random and unplaced contigs aside for now (see #7 (closed)), we should at least use the mappings for the ALT_REF_LOCI.
It seems NCBI Mapview mappings on ALT_REF_LOCI contigs are described as on CHROMOSOME_NAME|ALT_REF_LOCI_ACCESSION, for example:
13|NT_187592.1