Fixed: deleteMessage method in MessageController correctly
define message id
Added model attribute in showIn(Out)comingMessages methods of
MessageController to allow jsp to distinguish inbox and outbox.
Updated MessageController - added model attribute to form for sending message.
Added processing of tags in methods for adding and updating post.
Updated UserController:
added processing of avatarPath field from user register form;
remote images saved to local storage;
if any error occurs while image saving - return user to signup page with error
message.
Fixed avatar saving