Revision 163558

o Removed AuthenticationInfoProvider stuff
o Added ArtifactRepositoryFactory stuff to construct with AuthenticationInfo if possible.
o Added UserModelBuilder stuff for componentizing UserModel construction.
  -> DefaultUserModelBuilder has a configuration point 'userModelPath' which can redirect where it reads user.xml from (${user.home} is substitutable here).
o Added warning message to deployment plugin when deployment repo has no authentication info available.
o Added warning message for repos with null <id/> (auth info cannot be assigned here).
o Added a couple of debug-level messages for aid in debugging repo- and userModel-related problems.