Expand API for syncdaemon

[Natalia Bidart]

SyncDaemon should provide:

Connection related:
 * all the attributes and callbacks given by bug #573933
 * on_stopped, on_disconnected, on_offline callbacks

Queues related:
 * current state for content and meta queues (name suggestion: content_queue and meta_queue attribues)
 * on_content_queue_changed, and on_meta_queue_changed callbacks (already provided)

Volumes/shares related:
 * folders, shares_to_me, shares_to_others attributes
 * on_folders_changed, on_shares_to_me_changed, on_shares_to_others_changed callbacks
   (this is on hold until we define whether this will be always displayed to the user or not)

Public files related:
 * public_files attribute
 * on_public_files_changed callback (on hold, same disclaimer as above)

[Facundo Batista (facundo)]

- is_started: was done before

- is_connected: was done before

- is_online: was done before

- on_started: done in proposed branch, but called it on_started_callback; what
  about on_quited?

- on_connected: done in proposed branch, but called it on_connected_callback;
  what about on_disconnected?

- on_online: done in proposed branch, but called it on_online_callback; what
  about on_offline?

- content_queue: done in proposed branch

- meta_queue: done in proposed branch

- on_meta_queue_changed: this is already provided, but it's called
  meta_queue_changed_callback.

- on_content_queue_changed: this is already provided, but it's called
  content_queue_changed_callback.

Regarding Volumes, Shares, and public files, let's settle before the more
simple functionality.

[Facundo Batista (facundo)]

Ow, I discovered that the public files part would not be so easy...there's no such thing as "list public files" in syncdaemon tools.

[Facundo Batista (facundo)]

The "public files" stuff can not be done without support from u1-client... so I separated that part to other bug (#587960).

With all the branches merged, and this disclaimer, we can close this.