A few errors in the email widget

[Hamster-of-power]

Hi,
I am new to Github, so sorry, if this is not the "correct" way of reporting. There were a few errors that I would like to point out:

1. It says
   email_icon:set_image(path_to_icons .. "/mail-mark-new.png")
   That, png does not exist. Maybe try
   email_icon:set_image(path_to_icons .. "/mail-message-new.png")?

2. In the show_emails()function, you are using python. However, it requires python3. For python3, however, the print function of
   /home//.config/awesome/email-widget/read_unread_emails.py
   needs brackets in two places:
   line 10
   print("No messages found!")
   and line 16
   print("ERROR getting message", num)

Great program btw.

[streetturtle]

Thanks for the feedback! I created an issue from this post: #369