Document resteasy.servlet.mapping.prefix as init-param

It would be awesome if the reference guide mentioned that resteasy.servlet.mapping.prefix can be set as an init-param instead of a context-param. In fact, why isn't that recommended as the preferred way to set it? Setting it as an init-param is absolutely essential in order to include more than one RestEasy-based servlet in the same web.xml configuration.

From this Stack Overflow post, it is evident that this issue has affected others as well.