Add cancel button when adding to queue

[theAVator]

When adding a render to the render queue it would nice if the Add to Queue dialog box had a cancel/abort button to abort the addition of the render before the save is complete. 

Right now, because keyshot decided to change my custom folder locations to the keyshot defaults, I'm stuck waiting 45 minutes for a render to queue up which is 40 minutes longer than it should be. And I have to suffer through it because there is no way to abort the save, other than killing the program and having to reload the model and start over.

When the render queue is actively rendering there is a Cancel button, I can't imagine this would operate much differently. Kill the save action, and in this case, delete the GEOM and EXT files it's currently generating.