[en_US]GNOME Control Center(System Settings) lacks ability to change system's hostname. | [zh_TW] GNOME 控制中心（系統設定值）缺乏修改系統的 hostname 的能力

[Ｖ字龍(Vdragon)]

This is a bi-lingual bug report, please remove zh_TW translation directly when you want to change the content but unable to change the translations.

1. I expected there's a pre-installed GUI utility in Ubuntu to change hostname.
   我期待 Ubuntu 中存在一個預先安裝的用來修改 hostname 的圖形介面工具。
2. I expected it appears in GNOME Control Center(a.k.a. System Settings) -> Details -> "Device name" textbox
   我期待這個工具會出現於 GNOME 控制中心（也就是「系統設定值」）→詳細資料→「裝置名稱」文字編輯方塊中
    * In fact there's really a "textbox" at the location but is not editable and there's no "Unlock" button at that view.
      事實上在那個位置真的有一個「文字編輯方塊」但是它不能編輯且於那個視野中沒有「解除鎖定」按鈕可以解鎖它
3. I expected if I run GNOME Control Center as root (gksudo gnome-control-center) I can change my hostname
   我期待如果我以 root 的身份執行 GNOME 控制中心(gksudo gnome-control-center)我可以變更我的 hostname
    * In fact when GNOME Control Center run as root, the "textbox" really turn's into editable, but edit the content still won't apply to the system temporarily nor permanently.
    * 事實上當 GNOME 控制中心以 root 的身份執行時，那個「文字編輯方塊」真的變成可以編輯的樣子，但是編輯其內容依舊不會暫時或永久地套用到系統中。
4. I supposed there's many user having the same conclusion like me, so please help ;)
   我假定有許多使用者跟我一樣有相同的結論，所以請幫幫忙 ;)

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: gnome-control-center 1:3.4.2-0ubuntu0.11
ProcVersionSignature: Ubuntu 3.2.0-43.68-generic 3.2.42
Uname: Linux 3.2.0-43-generic i686
ApportVersion: 2.0.1-0ubuntu17.2
Architecture: i386
Date: Wed Jun 12 04:12:11 2013
ExecutablePath: /usr/bin/gnome-control-center
InstallationMedia: Ubuntu 12.04.2 LTS "Precise Pangolin" - Release i386 (20130213)
MarkForUpload: True
SourcePackage: gnome-control-center
UpgradeStatus: No upgrade log present (probably fresh install)
usr_lib_gnome-control-center:
 activity-log-manager-control-center 0.9.4-0ubuntu3.2
 deja-dup 22.0-0ubuntu4
 gnome-bluetooth 3.2.2-0ubuntu5
 indicator-datetime 0.3.94-0ubuntu2