improvements on email gui functionalities

Created a test-bed for sending out generic email using restructuredtext. Made a very simple sending-email client where you can specify TO/CC/BCC emails, FROM address, and PNG images inline into email. Uses Imgur for inlining images into email, and the GMail API to send emails.

v1.35 will arise ONCE I change the placeholder documentation, howdy_create_texts, to correct documentation for howdy_email_demo_gui.