SZ-87: Update Facebook SDK and documentation

hi @davidjed,
please take a look on this request. It includes: 

* FB sdk update: code base and pods dependence
* Documentation updates

Now we request *public profile* and *publish permissions* during our auth flow. Note that for successful auth we need only public profile request approval. It means that even if user decline publish request we will still be authenticated successfully. 
Then if user declined publish permissions we would get error and handle it when user would try to post something on FB: share, comment, like.  Error handling process is distributed. We will continue get single error with description  "Server returns error" like it was since this aggregated  possible error from all our 3td party  networks. And more concrete error will be posted via *options* instance that could be handled with new  methods in SZFacebookUtility.

Please review the scope and integrate it. Then you could create new release if you fill that this is good time ;) 
For new release *pod install* is required