message: Add mention support for Matrix->Discord
diff: @@ -123,7 +123,7 @@ export class DiscordBot {
  }
  public ProcessMatrixMsgEvent(event, guildId: string, channelId: string): Promise<any> {
  - let chan;
  + let chan: Discord.TextChannel;
  let embed;
  let botUser;
  const mxClient = this.bridge.getClientFactory().getClientAs();
  @@ -174,6 +174,7 @@ export class DiscordBot {
  if (botUser) {
  return chan.sendEmbed(embed, opts);
  }
  + const body = this.HandleMentions(event.content.body, chan.members.array());
  return chan.sendMessage(event.content.body, opts);
  }).then((msg) => {
  this.sentMessages.push(msg.id);
  @@ -196,6 +197,13 @@ export class DiscordBot {
  return "matrix-media." + mime.extension(content.info.mimetype);
  }
  + private HandleMentions(body: string, members: Discord.GuildMember[]): string {
  + for (const member of members) {
  + body = body.replace(new RegExp(member.displayName, "g"), `<@!${member.id}>`);
  + }
  + return body;
  + }
  +
  private GetRoomIdsFromChannel(channel: Discord.Channel): Promise<string[]> {
  return this.bridge.getRoomStore().getEntriesByRemoteRoomData({
  discord_channel: channel.id,
  