Improve Dispatcher

[z44d]

• Added compose function to run multiple bots

from tgram import TgBot, filters, compose
from tgram.types import Message

bot = TgBot("...", parse_mode="Markdown")
bot_2 = TgBot("...", parse_mode="Markdown")
FILTERS = filters.command("start")

@bot.on_message(FILTERS)
@bot_2.on_message(FILTERS)
async def on_start(_, m: Message) -> Message:
    return await m.reply_text(
        "**Hi**",
    )

compose([bot, bot_2])

• Move the class variables to TgBot.__init__
• Added stop method