Disable file grouping in ImageJ remote import plugin (rebased onto develop)



This is the same as gh-1081 but rebased onto develop.

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This should fix https://trac.openmicroscopy.org.uk/ome/ticket/12158 by disabling the ```Group files with similar names``` option when the remote importer plugin is being used.  ```Group files with similar names``` should still be enabled when using ```Plugins > Bio-Formats > Bio-Formats Importer```.