OAuth via ADFS with MFA support

[krutelp]

Add MFA support for OAuth via ADFS.
Add rudimentary message dialog to visualize necessary MFA action.

[krutelp]

Closes SourceForge #725 O365Modern with MFA PhoneApp does not work

[mguessan]

Thanks for your contribution, will merge this after a few checks

[mguessan]

Merged first commit, need some more time for the second one: O365Authenticator is supposed to be headless so user interaction was not an option.

However for SMS based authentication there is no way to provide code without such interaction
=> we wil need to support both graphical and command line user interaction

See certificate management for an example:

if (Settings.getBooleanProperty("davmail.server") || GraphicsEnvironment.isHeadless()) { // headless or server mode isCertificateTrusted = isCertificateTrusted(x509Certificates[0]); } else { isCertificateTrusted = AcceptCertificateDialog.isCertificateTrusted(x509Certificates[0]); }

[krutelp]

I suggest to show graphical/console information also for case PhoneAppNotification. User should be informed about required action on smartphone. Is in graphical mode possible to show answer from server in some kind of HTML/JavaScript Java viewer in order to reduce MFA implementation effort?