Allow functor attachables to have one or two args
Properly track published actors, add unpublish

Extend the BASP broker to monitor published actors and automatically unpublish
them using attachables. Also add missing io::unpublish function to allow users
to release ports manually. Fixes #189 and closes #197.
Fix timeout handling for event-based actors
Restrict `duration` to accept only integral values

Rather than implicitly casting floating points to integrals, `duration` now
verifies its input to be integral via `static_assert`. This patch also
streamlines the implementation of `duration`, reducing its code size.
Remove unused code.
Handle disconnect during handshake, fix #192
Port CAF to FreeBSD 10.

It suffices to define a few includes to make CAF work with FreeBSD 10.
Merge branch 'master' into develop
Update links to submodules
Merge branch 'develop'
Change version to 0.11.2
Add `unpublish` function to manual
Update PDF version of manual