Running the Bjorne shell as a command

Peter and gchii brought up the issue that the Bjorne interpreter should be invokable as a JNode command. For example, as

Runtime.exec("bjorne", "-c", "sort < list.txt > sorted-list.txt");

Two things are required to make this work:

1. A command class for the Bjorne interpreter. It is currently only usable as an embedded interpreter within the CommandShell.
2. Infrastructure to make Runtime.exec(...) and friends work on JNode. I think that the desired behavior would be to run the command using the current CommandInvoker.