Make a main-loop object with associated helper functions to handle async
methods.
rtloop -> data_loop
Handle async results a lot better.
Remove REMOVE_MEM command. We don't need it.
Handle stream memory updates better.
Pass the client object around, it's easier to deal with than the sender
id.
Fix the ASYNC return check
Don't overwrite the fds of a pollitem, instead keep an index of their
position in the global fd array.