Improve gmail warning

[aenario]

The new code renders to :

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Gmail considers connection using username and password "less secure", but provides poor alternatives for open source applications. If you don't have 2-Step Verification enabled, you can get around this obstacle by:

• Click on this link: https://www.google.com/settings/security/lesssecureapps
• If you have several gmail accounts, make sure you are connected as xxxxxx@gmail.com.
• Enable access for "less secure" apps.

If you still can't connect, you might need to use the unlock captcha from the following link: Display unlock captcha.

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Warning : need to fix transifex before publishing

[m4dz]

Google, same weird-usual-suspect… Thanks!