Google now requires TLS minimum. Segfault on erroneous deleteLater() call

[lpds-tarvos]

First off, excellent library very straight forward and I got it to work in no time! Here are a few tweaks I did have to make incase anyone else has problems.

ISSUE 1: TLS min requirements
add the following statement on line 167:

socket->setProtocol(QSsl::TlsV1_0OrLater);

socket->startClientEncryption();
if(!socket->waitForEncrypted(timeout))
{
qDebug() << socket->errorString();
state = Close;
}
................................................................
ISSUE 2: You may have to adjust your gmail account settings to allow insecure apps to login on your account. Also 2 factor auth must be disabled in order for it to work
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ISSUE 3:
On line 251 you call deleteLater() on the MainWindow object itself causing a segfault. This could also be related to the the function that looks a bit iffy in MainWindow::sendMail. At the very least its a memory leak.

Make Smtp a class member variable and use it as a stack allocated object rather than a heap allocated one. Then you wont have to worry about the dangling pointer.