-代表原来api，+代表修改后的api。 @Deprecated代表已过时的api，后面会带着替代的api 新增加接口EMOptions

EMOptions:
+     public void setAutoTransferMessageAttachments(boolean transfer);
+     public boolean getAutoTransferMessageAttachments();

+     public void setAutoDownloadThumbnail(boolean autodownload);
+     public boolean getAutodownloadThumbnail();

新增加接口EMCallOptions

EMCallOptions:
+     public void setCallAudioSource(int source);