UI: supports reboot from context menu

UI: supports reboot from context menu

When a malfunction of emulator occurs, such as no response from the guest OS,
what a developer can do is selecting "force close"
and restarting from emulator manager.

In order to avoid the inconvenience of doing it, reboot menu is added.
It is working directly to hardware after requesting sync() to guest OS

         ----------------
         | Context menu |
         ----------------
         |   reboot     |
         ----------------                         ----------
                |                                 | emuld  |
     ------------------------                     ----------
     | 1. send sync message |   ------------->    | sync() |
     | 2. start a timer     |                     ----------
     ------------------------
               | The timer expires after 1s
   -------------------------------
   | qemu_system_reset_request() |
   -------------------------------

Conflicts:
	tizen/src/extension/ui/resource/skins/tv-1080x1920/layout.xml
	tizen/src/extension/ui/resource/skins/tv-1920x1080/layout.xml
	tizen/src/extension/ui/resource/skins/tv-2560x1080/layout.xml

Change-Id: I3c3c31c2cc19065f53b620d83c79e68e0183db53
Signed-off-by: Jinhyung Choi <jinh0.choi@samsung.com>
(cherry picked from commit 14fc61baff1e8b48cbcb810a8392a1ac601f2511)