Hide all conversations

This is an account-level operation and should not appear in an individual conversation's action menu:

[[OIMManager manager] hideAllConversationsWithOnSuccess:^(NSString *data) {
    [self clearConversationList];
}
                                              onFailure:nil];

Before calling it, clear page state and pagination references associated with the current account. Success means that the hide request has completed; it does not mean that messages or chat relationships were deleted. The pinned version's deprecated deleteAllConversationFromLocalWithOnSuccess:onFailure: method is not part of the public documentation.