- Migrated to twitch helix api for stream notifications

- Added 2 new fields to creds.yml -> TwitchClientId and TwitchClientSecret
- Users now have to provide them in order to use twitch stream notifications as Twitch is shutting down old api on 18th of February 2022
- Possibly fixed some issues with streams randomly getting cleared
- Added an incomplete trovo stream notification provider

src/NadekoBot/Modules/Searches/StreamNotification/StreamNotificationCommands.cs

@@ -16,9 +16,6 @@ public partial class Searches
         public StreamNotificationCommands(DbService db)
             => _db = db;
 
-        // private static readonly Regex picartoRegex = new Regex(@"picarto.tv/(?<name>.+[^/])/?",
-        //     RegexOptions.Compiled | RegexOptions.IgnoreCase);
-
         [Cmd]
         [RequireContext(ContextType.Guild)]
         [UserPerm(GuildPerm.ManageMessages)]