Merge remote-tracking branch 'origin/remove-repositories'

This removes the frowned-upon <repositories> section from the central
part of pom-scijava (it is still in a profile).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Activate auto-releasing when deploying to Sonatype

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