Update examples

examples/echo_bot.py

@@ -0,0 +1,17 @@
+from pyrogram import Client, Filters
+
+"""This simple echo bot replies to every private text message"""
+
+app = Client("my_account")
+
+
+@app.on_message(Filters.text & Filters.private)
+def echo(client, message):
+    client.send_message(
+        message.chat.id, message.text,
+        reply_to_message_id=message.message_id
+    )
+
+
+app.start()
+app.idle()