Sharing permissions

[jefflunt]

UPDATED role descriptions:

• Owner: Manages access to the LogBook. Manages the structure of the data. Manages sections, and attributes available on those sections. Can do anything to the WorldObjects in a LogBook that they own.
• Editor: Manages data correctness. Can do anything to the WorldObjects (add/edit/delete) in a LogBook on which the editor role has been granted.
• Public: Read-only access.

Additionally, you can make a LogBook public, which allows any user (even anonymous, not logged in users) the ability to see the contents of the LogBook. There is NO public or anonymous read-write access of any kind.

[jefflunt]

Four issues:

• done - My editor user, in testing, can't actually edit, add, or delete any WorldObjects
• done - The login screen redirects to the new_log_book action, even if I have LogBooks shared to me (e.g. my "owned" log books are still zero)
• done - The list of public log books on the index page is missing the extra %td cell where the "x" or share icon would otherwise go. This only seems to happen when a user is logged in.
• We need to remove "x" icons next to WorldObjects, and links to view WorldObjects, if all you have is read (public) access to a log book

[jefflunt]

Forgot that I haven't yet implemented the control to mark something as public.