[security-dev] PicketLink restructure

In the interests of presenting a clear message to our developers, one of the steps we'll be taking is to consolidate the various PicketLink projects into a single project and presenting this as the "go to" solution for application security. For now I've merged the CDI and IDM subprojects (these are now submodules of the PicketLink project, with "CDI" renamed to "Core") and the plan is to eventually merge the social and federation modules also. You can find the new GitHub repository here: https://github.com/picketlink (renamed from picketlink-cdi) and the picketlink-idm repository has now been deleted. For anyone working on these modules, please use the new repository from now on. Thanks! Shane