ShellPkg: Added the Ctrl based hot key and changed text editor's UI.

ShellPkg: Added the Ctrl based hot key and changed text editor's UI.

* Add Ctrl-E hotkey for help
* Add Ctrl based hotkey alternatives to function hotkeys
* Don't show hotkey help on the main screen
* Change the file buffer's row count for display to adjust the new screen format
* Change the edit status bar location, the new edit status bar is in the last line
* Change the location of the edit bar, the new edit input bar is in the last line

Signed-off-by: kidzyoung
reviewed-by: jcarsey
reviewed-by: jljusten
reviewed-by: jiang

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12036 6f19259b-4bc3-4df7-8a09-765794883524