Unload ofile before linking (Fix #10216)

Use an unlinked original file object (i.e. a proxy) for
linking the stdout and stderr. The files were previously
being uploaded, just linked. This is likely a result of
the files being modified on save to calculate the sha1,
but is not directly an FS issue.
Pass context to script helper (Fix #10970)

ScriptI was failing to pass the Ice.Current.ctx
value down to the script helper for use with
`Executor.execute(Map<String, String>, ...)`

bin/omero script replace now works as expected

Note: it still modifies the ID of the script!
Actively load user group on ScriptRepoHelper.update

Conflicts:
	components/server/src/ome/services/scripts/ScriptRepoHelper.java
Merge pull request #1464 from joshmoore/original_file_rebases

Original file rebases