Bug

- Fixed bug where specifying an ID of 0 yielded all completed/deleted tasks
  (thanks to greenskeleton).
Deprecated Features

- Marked the push/pull/merge features as deprecated.
L10N

- Removed unused strings.
Code Cleanup

- The 'diagnostics' command no longer generates 1000 UUIDs as a uniqueness
  test, because libuuid is now mandatory.
Documentation

- Cleaned up a few old references.
Documentation

- Rewrote task-sync(5) man page.
Documentation

- Cleaned up obsolete references.