Add source code repository information

It is easier to modify or delete that section than to research how
to specify the SCM information in Maven projects from scratch.

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

It is easier to modify or delete that section than to research how
to specify the involved developers in Maven projects from scratch.

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