Document POST/PUT supported methods for creating entities (e.g. entitlements)

[gberche-orange]

Seems from https://www.openhub.net/forums/10/topics/7860#post_22594 that POST method is supported for some resources, such as entitlements, but it is not currently documented.

In particular, how can REST clients generate the entitlement id ? Is it a sequential Ids ? Can any UUID be used ?