Move gene_mapping generation to this repo

[glass-ships]

Move https://github.com/monarch-initiative/monarch-gene-mapping/ code into this repository

• [ ] Reduce/remove CLI code
• [ ] Condense to one or two script files
• [x] Add Jenkinsfile to generate mappings and upload to data.mi.org
• Later update monarch ingest to grab all mappings from data.mi.org

[glass-ships]

Will look at this for December milestone or something