Updater (Swing): focus the username and password fields

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add scijava-common as an explicit dependency of the ssh uploader

It was a transitive dependency already, but should be explicit because
classes from scijava-common are used directly.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Fix a compiler warning

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Expose more attributes of the FilesUploader

This change is needed for the upcoming WebDAV uploader.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Start a WebDAV-based uploader for the ImageJ updater

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
WIP: Add a test for the WebDAV uploader

TODO: turn it into a JUnit test, triggered by java properties providing credentials.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
wip