- restore some CKGlobals behavior because it will cause runtime exception.
- move some classes from CmdHelper to UnvirtContext to make CmdHelper more common to use.
- output warning string when fail to get utf8 or ordinary string.
- fix build issue in Unvirt and LibCmo
- due to we use UTF8 string. the accessible value generator in EnumsMigration need to be changed at the same time.
- remove string helper in Unvirt because we no longer need it.
- fix usage error of ckid getter in bmap wrapper.
- fix CKObject flag init value error.
- fix CKFileWriter writing empty object name error.
- regulate some statement.
