[Windows] add some feedback when selecting a project from the splash screen.
On windows.. when selecting with double click a file name on the splash screen... everything is freezing, after a while (10 seconds?) the project will be loaded .. but for 10 seconds the user doesn't know if Kdenlive is simply crashed.. or if there is an issue.... or whatever other (bad) thing...
maybe can be bettere to add a text, a label, a message box.. a small loading window.... with written on it: "Loading..." just to put the user in the position of waiting for something.. (whitaout opening task manager... clicking randomly.. pressing CTRL ALT CANC.. .. relauncing kdenlive)

issue