- another example of zsh supremacy in shell world! fixed 5 yrs old flaw

- another example of zsh supremacy in shell world! fixed 5 yrs old flaw
  introduced in rev. 8719 that neither pdksh nor mksh handled properly,
  not to mention bash - such process backgrounding caused, when called
  from functions/run_cmd (i.e. during service network start), I/O wait
  for STDOUT of 'background' job despite >/dev/null redirects; this
  effectively leads to 2 seconds delay for each interface at system
  startup, cumulating to minutes of pointless waiting on heavy networked
  machines! There is alternate workaround: { { sleep 2; } & } >/dev/null
  that works as expected under pdksh or mksh, but requires additional &
  for zsh and doesn't fix bash behaviour, so please do not touch _THIS_
  solution without comprehensive research! -- Aug 29th, 2012, /me
  Note: this happens due to $() capture, so plain ifup isn't enough.

svn-id: @12592