Add multi-user support

Add multi-user support

Note that offending paths ("/opt/usr/apps") in the file sample.xml were
not removed since this file is neither used nor part of the
generated RPM. As the name of the file suggest it, it simply is a
sample.

Also correct some RPMLINT warnings/errors:
+ set a valid license tag in spec file
+ set a valid group tag in spec file
+ call ldconfig during post install (%post) and post uninstall (%postun)
  processes in spec file

Bug-Tizen: PTREL-345
Change-Id: I1b4b00ddcf8d51c98f67e5ae268e0ca0503de176
Signed-off-by: Kévin THIERRY <kevin.thierry@open.eurogiciel.org>