Sync oslo service module

Sync oslo service module

This does a full sync of the oslo.service module.  Note
that we've cherry picked some critical bug-fix changes
to this module already, this commit just syncs the full
module properly and gets us up to date where we should be.

Current HEAD in OSLO:
-----------------------
commit:  d5edda00b4eca65d57f94bd0ac1b790e6d1f732e
Date:    Wed Apr 22 19:49:00 2015 +0000
Merge "service child process normal SIGTERM exit"

Changes merged with this patch:
---------------------------------
d5edda00 - Merge "service child process normal SIGTERM exit"
702bc569 - service child process normal SIGTERM exit
64b5819e - Revert "Revert "Revert "Optimization of waiting subprocesses
           in ProcessLauncher
f5646edc - Revert "Revert "Optimization of waiting subprocesses
           in ProcessLauncher
d23b6589 - Revert "Optimization of waiting subprocesses in ProcessLauncher"
593005b7 - ProcessLauncher: reload config file in parent process on SIGHUP
f29e865d - Store ProcessLauncher signal handlers on class level
bf92010c - Optimization of waiting subprocesses in ProcessLauncher

NOTE: Commit 702bc569 was actually pulled in with commit d73ac96d .
      We shouldn't have merged that individual commit.  I include the
      commit here to document Oslo level that the service module is at
      cumulatively between that commit and patch.

Change-Id: I613ba5ba442cf533c0f68d06281d117fbac20bd6