Updater (cmd-line): Add the --simulate option to upload-complete-site

This option allows a dry run before the real thing.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Updater (cmd-line): update dependencies with upload-complete-site

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Updater (upload-complete-site): special-case ImageJ's tools.jar

For ImageJ 1.x, we need to retain jars/tools.jar...

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Updater (upload-complete-site): fix handling of obsolete dependencies

Earlier, we tried to remove all the dependencies on the same update
site as the dependencee (that needs to be uploaded)." -m "This falls
short of a proper solution for a number of reasons: it does not work
for non-.jar files, it does not leave manually-added dependencies
alone, and it fails to adjust unchanged files whose dependencies are
found in different files.

Except making sure that all classes are still found for unchanged files
-- which the updater never did -- this change addresses these concerns.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>