Web Subscribers; Secret Key can now be entered

Previously the Web Subscriber's Secret Key could not be directly entered, it could only be generated. You may now enter the Secret Key, which allows you to use your own keys.

In addition the "Generate" button's icon has been updated and a tooltip added for the Secret Key.

Note, the minimum length of a Secret Key is 30 characters and the maximum length is 100 characters.

In addition the Secret Key field did not wrap over two lines on high DPI monitors - this has been fixed.