Create document with requirements for the REWS group re IP and licensing

[mcourtot]

DU needs to document requirements they have for licensing and communicate these to the IP subgroup of REWS. Discussed at the GA4GH meeting:

• trademark on the "GA4GH DUO" name: we wouldn't want others to release a product called "GA4GH DUO"
• how much modification do we want to allow on the ontology? Discussion around CC-BY-ND, but would DU really want an ND one? The idea of DUO is to allow people to extend it and use pieces of it in their own products, while preventing modification and reminding of their IRIs

cc @mellybelly