Mashup TGF and WHO data

Use The Global Fund[1] database of funding together with WHO's Global
Health Observatory Data Repository[2]. API endpoints are:

  /api/stats/diseases.json     # List of diseases
  /api/stats/diseases/:id.json # Funding and death summary

[1]: http://www.theglobalfund.org/
[2]: http://apps.who.int/gho/data/?theme=main
Merge pull request #1 from UnboxedSchrodingers/mashup-tgf-and-who-data

Mashup TGF and WHO data