Bug: Batch Installer does not run merges if mod installation is canceled

[Mgamerz]

If mod installation is canceled in a set of batch mods, the merges that should run don't appear to be, according to the logs. They are queued as batch result instead that attach to the next shown panel. We must ensure BatchPanelResult is handled on the final close of all panels.

It might be best to build in some code to detect this and breakpoint always on it.