[DGD] Kotaka v0.52

[Raymond Jennings]

More internal housekeeping.

Please check the commit log, this is just a maintenance release.

There are some deprecations upcoming.  We will no longer make use of
the global callout suspension process.  In its place, hooks will be
added to enforce begin and end of task processing.

Also, henceforth, every upgrade should be followed by a global rebuild.

git://github.com/shentino/kotaka.git