-doxygen, indentation

git-svn-id: https://gnunet.org/svn/gnunet@33791 140774ce-b5e7-0310-ab8b-a85725594a96
-remove logic for somewhat overkill check to see if session object is valid

git-svn-id: https://gnunet.org/svn/gnunet@33792 140774ce-b5e7-0310-ab8b-a85725594a96
-simplify logic, just use clearly working direct method to extract session from server's client handle

git-svn-id: https://gnunet.org/svn/gnunet@33793 140774ce-b5e7-0310-ab8b-a85725594a96
-indentation, doxygen

git-svn-id: https://gnunet.org/svn/gnunet@33794 140774ce-b5e7-0310-ab8b-a85725594a96
use session map instead of DLL

git-svn-id: https://gnunet.org/svn/gnunet@33795 140774ce-b5e7-0310-ab8b-a85725594a96