Room preview of email invitation: Replaced [RoomVC displayEmailInvitation] by [RoomVC displayRoomPreview], a more generic function that handles email invitation and simple link to a room

Connected AppDelegate to this method

Vector/Model/Room/RoomPreviewData.h

@@ -0,0 +1,63 @@
+/*
+ Copyright 2016 OpenMarket Ltd
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "RoomEmailInvitation.h"
+#import "MXSession.h"
+
+/**
+ The `RoomEmailInvitation` gathers information for displaying the preview of a
+ room that is unknown for the user.
+
+ Such room can come from an email invitation link or a link to a room.
+ */
+
+@interface RoomPreviewData : NSObject
+
+/**
+ The id of the room to preview.
+ */
+@property (nonatomic, readonly) NSString *roomId;
+
+/**
+ In case of email invitation, the information extracted from the email invitation link.
+ */
+@property (nonatomic, readonly) RoomEmailInvitation *emailInvitation;
+
+/**
+ The matrix session to show the data.
+ */
+@property (nonatomic) MXSession *mxSession;
+
+/**
+ TODO
+ */
+@property (nonatomic, readonly) NSString *roomName;
+@property (nonatomic, readonly) NSString *roomAvatarUrl;
+@property (nonatomic, readonly) NSString *roomTopic;
+
+/**
+ Contructors.
+ 
+ @param roomId the id of the room.
+ @param emailInvitationParams, in case of an email invitation link, the query parameters extracted from the link.
+ @param mxSession the session to open the room preview with.
+ */
+- (instancetype)initWithRoomId:(NSString*)roomId andSession:(MXSession*)mxSession;
+- (instancetype)initWithRoomId:(NSString*)roomId emailInvitationParams:(NSDictionary*)emailInvitationParams andSession:(MXSession*)mxSession;
+
+@end