Add the foreach ... do command.

Introducing the foreach command. You can now loop over several ids and
run a command like this:

  foreach 1 2 5-10 do files

This will result in the command 'torrent <id> files' will be executed
for each of the ids 1, 2, 5, 6, 7, 8, 9, 10. This way, you can control
even large amount of torrents with a simple command.
Add a torrent <id> rm sub command

This is a convinient alias for the rm command, developed to be able to
leverage it in combination with the foreach command, like this:

 foreach 1 2 100-200 do rm

Or, if you want to remove the actual data, you can, just like with
the regular rm command, do:

 foreach 1 2 100-200 do rm -d

Of course, you can use it without foreach as well. The following two
commands are equivalent:

 rm 123
 torrent 123 rm
Update user manual / command line help texts