First variant of authorisation (without permissions).
Added enum for permissions, authorisation can now take not only default permissions.
Added authCallbacks.
Got info about current user.
Example of using FBAPIWrapper with info about current user and current user's newsfeed.
Added comments.
Added posting news.
Deprecated method withou posting.
Deprecated method withou posting(for interface and impl).
FBNode constatnts and example.
DO NOT HARDCODE SUBNODES, USE FBNode!
merge conflict resolved