Add support for devmode-installed services to mojoservicelauncher

:Release Notes:

run-js-service now looks for roles files in /var/palm/ls2-dev, for services started from /media/developer. This should allow devmode-installed service to launch.

:Detailed Notes:

This is a trivial change to the path that roles files are loaded from.
:Testing Performed:
installed package, non-devmode services still run fine. Need to check with a devmode-installed service when I have developer mode enabled.

:QA Notes:

:Issues Addressed:
[GF-13324] Nodejs must support devmode-installed services with roles/service files at /var/palm/ls2-dev/*

Open-webOS-DCO-1.0-Signed-off-by: Mark Bessey <mark.bessey@lge.com>

Change-Id: I40a25bf4967c86e216e4407265dfcecccc16dfb0
Reviewed-on: https://g2g.palm.com/3355
Reviewed-by: Build Verification
Reviewed-by: Steve Lemke <steve.lemke@lge.com>
Tested-by: Mark Bessey <mark.bessey@lge.com>
Reviewed-by: Mark Bessey <mark.bessey@lge.com>