media group messages refactoring

src/main/kotlin/com/github/insanusmokrassar/TelegramBotAPI/types/message/ChannelMediaGroupMessage.kt

@@ -8,7 +8,7 @@ import com.github.insanusmokrassar.TelegramBotAPI.types.message.abstracts.Messag
 import com.github.insanusmokrassar.TelegramBotAPI.types.message.content.abstracts.MediaGroupContent
 import org.joda.time.DateTime
 
-data class MediaGroupMessage(
+data class ChannelMediaGroupMessage(
     override val messageId: MessageIdentifier,
     override val chat: Chat,
     override val date: DateTime,
@@ -17,4 +17,4 @@ data class MediaGroupMessage(
     override val editDate: DateTime?,
     override val forwarded: ForwardedMessage?,
     override val replyTo: Message?
-) : Message, MediaGroupMessage
+) : MediaGroupMessage

src/main/kotlin/com/github/insanusmokrassar/TelegramBotAPI/types/message/CommonMediaGroupMessage.kt

@@ -17,4 +17,4 @@ data class CommonMediaGroupMessage(
     override val editDate: DateTime?,
     override val forwarded: ForwardedMessage?,
     override val replyTo: Message?
-) : Message, MediaGroupMessage, FromUserMessage
+) : MediaGroupMessage, FromUserMessage

src/main/kotlin/com/github/insanusmokrassar/TelegramBotAPI/types/message/RawMessage.kt

@@ -210,7 +210,7 @@ data class RawMessage(
             content ->
             media_group_id ?.let {
                 when (from) {
-                    null -> MediaGroupMessage(
+                    null -> ChannelMediaGroupMessage(
                         messageId,
                         chat,
                         date.asDate,