--create now outputs an extra blank line.

This ensures that a configuration file entirely made up off
automatically created configurations will stay nice and clean with extra
whitespace between each profile.
Removing definition of $options in update.rb.

The reason for the unnecessity of tihs definition is that update.rb is
never supposed to be called on its own, but through the use of --update
argument to rmonitor.rb.
Redirect stdout instead of using IO#popen.

I find it more comfortable to now create a new process to capture
output. This redirects standard output to a variable, which captures the
created configuration, by using StringIO.