restructured example and added readme

examples/multi-transport-chatbot/Dockerfile

@@ -0,0 +1,8 @@
+FROM dailyco/pipecat-base:latest
+RUN apt-get update && apt-get install ffmpeg -y
+
+COPY ./requirements.txt requirements.txt
+
+RUN pip install --no-cache-dir --upgrade -r requirements.txt
+
+COPY ./bot.py bot.py