rush 0.4

[Adam Wiggins]

rush 0.4 is in rubyforge now. Changes since 0.3:

- Rush::Box#processes returns a ProcessSet, which behaves like an
array, but offers a filter method, and can execute bulk commands like
kill and alive?. So what we previously written as:

processes.find_all_by_cmdline(/mongrel_rails/).each { |p| p.kill }

...is now:

processes.filter(:cmdline => /mongrel_rails/).kill

- Daemonize shell commands: bash 'some_daemon', :background => true
This was actually a pretty challenging feature to implement in a way
that made it compatible with the other features of bash, i.e. :user
and :env.

- Pass args to rush on the command line to execute a one-off, like this:

rush 'processes.filter(:command => "ruby")'

- Other misc small fixes and improvements, as usual.