TODO list for MeshLink
----------------------

* meshlink_join():
  - add checks that we only join another mesh if we did not connect to any other node before.
  - only allow meshlink_join() when the library thread is not running.
  - remove old host config file if the invitation gave the node a different name.
  - how to handle nodes that are part of one mesh and want to join another?

* meshlink_leave()?
  - leaving a mesh is basically starting all over again, with new private keys?

* Allow meshlink_open() to be called with a NULL name, in anticipation of meshlink_join().
  - Do not allow meshlink_start() if no Name is set.

* Add autoconf/automake stuff to call Doxygen.

* Write a manual
  - Add introduction and walkthrough how to use MeshLink in an application to
    the doxygen manual.
  - Explain what MeshLink does and how it should be used in the application
  - Import examples into the manual?
  - List possible ways of synchronisation between application and library threads
    - simple polling
    - pthread_cond?
    - pipe() to signal an event loop of the application's choice
    - whatever equivalent(s) there are on Windows

Not finished but being worked on:
---------------------------------

* Provide thread-safety to functions that return pointers to meshlink_node_t.
  - The mesh->nodes tree can be updated by the library thread at any time,
    so it must be protected by a mutex or rwlock.
  - Individial node_t's must never be freed or moved except in meshlink_close().
  - Check all public API functions.

* Write a test suite for the library.

* Add a "channel" library to MeshLink.
  - Support multiple TCP- and UDP-like streams between two nodes.