Port from sysV rc script based to systemd based

Port from sysV rc script based to systemd based

To port to systemd based, these changes made:

1. config/* remove all the extra "export" keyword, since "EnvironmentFile" in
   systemd does not need that;
2. Remove the run-chg-ani.in and its link in rc2, we will babysit
   charging-animation by systemd.
3. Add charging-mode.service and charging-mode.target, also create a link of
   charging-mode.service in charging-mode.target.wants

Signed-off-by: Yin Kangkai <kangkai.yin@intel.com>
[Polishes and fixes]
4. We will keep all the sysV rc srcripts;
5. Separate platform specific environment variables into
   /etc/sysconfig/charging-animation;
Signed-off-by: Jacek Migacz <j.migacz@samsung.com>
Signed-off-by: Karol Lewandowski <k.lewandowsk@samsung.com>