Add a skeleton for init scripts

Add a skeleton for init scripts

Add a skeleton for init scripts, the original structure is from
/etc/init.d/skeleton of Ubuntu 10.10, it is in sysvinit_2.87dsf, so add
the COPYRIGHT(GPLv2) of sysvinit_2.87dsf. Modified the original skeleton
a lot to make it as easy as possible, just use posix shell command, and
have tested it with core-image-minimal.

* The skeleton implements the following actions:
  - start, stop, restart, status, try-restart and force-reload.
    # force-reload is a alias of try-restart.

  - not implements reload, since only a few programs have it, just leave
    it as placeholder.

* Add /usr/sbin/skeleton-test to test /etc/init.d/skeleton

* The /etc/init.d/skeleton can be run and output the example messages:
  1) #./skeleton start (test start)
     Starting skeleton ...

  2) #./skeleton start (test start again when running)
     skeleton already running (1078).

  3) #./skeleton status (test status when running)
     skeleton is running (1078).

  4) #./skeleton stop (test stop)
     Stopped skeleton (1078).

  5) #./skeleton stop (test stop again)
     skeleton is not running; none killed.

  6) #./skeleton status (test status when stopped)
     skeleton is not running.

  7) #./skeleton restart (test restart when running)
     Stopped skeleton (1128).
     Starting skeleton ...

  8) #./skeleton restart (test restart when stopped)
     skeleton is not running; none killed.
     Starting skeleton ...

  9)  try-restart (or force-reload) means restart the service if the
      service is already running

     #./skeleton try-restart (test try-restart when stopped)
     skeleton is not running; none killed.

     #./skeleton try-restart (test try-restart when running)
      Stopped skeleton (1181).
      Starting skeleton ...

* Have used syslogd to test it in a real world(with both
  core-image-minimal and core-image-sato)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>