Add new cases for gmail-gmail

__tests__/files/gmail-gmail/README.md

__tests__/files/gmail-gmail/chrome-chrome/01/received.eml

__tests__/files/gmail-gmail/chrome-chrome/01/sent.eml

__tests__/files/gmail-gmail/chrome-chrome/02/received.eml

__tests__/files/gmail-gmail/chrome-chrome/02/sent.eml

__tests__/files/gmail-gmail/chrome-chrome/03/received.eml

__tests__/files/gmail-gmail/chrome-chrome/03/sent.eml

__tests__/files/gmail-gmail/chrome-chrome/04/received.eml

__tests__/files/gmail-gmail/chrome-chrome/04/sent.eml

__tests__/files/gmail-gmail/chrome-chrome/05/received.eml

__tests__/files/gmail-gmail/chrome-chrome/05/sent.eml

__tests__/files/gmail-gmail/chrome-chrome/06/received.eml

__tests__/files/gmail-gmail/chrome-chrome/06/sent.eml

__tests__/files/gmail-gmail/chrome-chrome/07/received.eml

__tests__/files/gmail-gmail/chrome-chrome/07/sent.eml

__tests__/files/gmail-gmail/chrome-chrome/08/received.eml

__tests__/files/gmail-gmail/chrome-chrome/08/sent.eml

__tests__/files/gmail-gmail/empty

__tests__/files/gmail-gmail/one/04/r_htmlContent.html

__tests__/files/gmail-gmail/one/05/r_htmlContent.html