o.c.scan: Remove o.c.scan.custom, move CommentCommand into o.c.scan

o.c.scan.custom was started as example how to add commands via extension
point. Basic o.c.scan already shows this, since all commands are based
on extension point...
o.c.scan: Update version to 3.2.1, update javadoc
Merge remote-tracking branch 'origin/3.2.x' into 3.2.x
o.c.sns.pvnames: Adapt to change in AutoCompleteResult
SNS: Use o.c.examples