submit/tizen_2.1/20130406.112529

[Version] 0.1.23
[Project] GT-I8800
[Title] Release wrt-installer_0.1.23
[Issue#] N/A
[Problem] N/A
[Cause] N/A
[Solution] Remove GUID and refactoring update installing mode
[Issue#] N/A
[Problem] Fail to add "nodisplay" in the config.xml
[Cause] Missed xsd element
[Solution] Add "nodisplay" in the tizen:setting
[Issue#] N/A
[Problem] Widget's content was not encrypted after updating it though
encryption was enabled.
[Cause] Encryption step was not included in the update task.
[Solution] Include encryption in the update task.
[Issue#] N/A
[Problem] Method decalred but not defined.
[Cause] N/A
[Solution] Remove method declaration.
[Issue#] N/A
[Problem] N/A
[Cause] error code is redefined.
[Solution] if error occur in installer, error code should send to package manager.
so modify error code and send logic.
[Issue#] N/A
[Problem] N/A
[Cause] N/A
[Solution] remove unused code about wac.
[SCMRequest] N/A