better GUI for "remove upload index" menu item

[xulman]

consider the recent functionality of scijava, namely

https://github.com/imagej/tutorials/tree/master/java/dynamic-commands/src/main/java

that can create dialog of variable number of items... possibly....

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create a list of discovered files (wanted) rather than a drop-down choice box (current situation) that only lists discovered files and selecting them has no effect on anything... which user will likely not realize