Add minimal example script and update README with warning about date synchronization

examples/README.md

@@ -1,3 +1,6 @@
 # Examples
 
 - [Recommended usage with NTP time synchronization](example.py)
+- [Minimal example](minimal.py)[^warning-date]
+
+[^warning-date]: Warning: this will send an email with a very wrong date if the time was not synchronized on the device.

examples/minimal.py

@@ -0,0 +1,25 @@
+from micromail import MicromailClient
+
+# Create an SMTP client
+client = MicromailClient(
+    host="mail.example.com",
+    port=465,
+    ssl=True,
+)
+
+# Connect to the server
+client.connect()
+# Login to the server
+client.login("example@example.com", "password")
+# Initialize a new message
+client.new_message("example@example.org")
+# Set message headers
+# WARNING: This will send a message with a very wrong date if time is not correct on the device
+# --- It might be rejected by the mail server
+client.headers()
+# Write message content
+client.write_line("Hello world!\n")
+# Send message
+client.send()
+
+client.quit()