Files whose metadata changed must be marked for upload explicitly

Otherwise, even the file name jars/bsh.jar in Fiji will be mistaken for
an uploadable change.

This happens to fix the bug that prevented third-party update sites from
being uploaded to, reported by Gabriel Landini, Ignacio Arganda-Carreras
and Jay Unruh.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
A metadata change still needs an uploadable update site to be uploadable

Even if there is a changed file name, it is not enough to allow marking
the file for upload: the associated update site also needs upload
information.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add a regression test for personal update site uploading

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Merge branch 'upload-to-personal-site'

This fixes a bug preventing uploads to any third-party update site,
including personal update sites.

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