Don't dismiss while hovering

[Evanion]

Expected behaviour

When a user is hovering over a toast, the toast shouldn't be dismissed, even if it times out. When the user moves mouse of the toast, it should be dismissed after a delay.

Actual behaviour

The toast gets dismissed even if the user is hovering over the toast message.

Explanation

This allows the user to delay dismissal of a toast, in case they need additional time reading the message.

[ferrao]

@Evanion PR?