add constants of status and enable status to class IData
add constants of status and enable status to class IData

Status and Enable Status is(will be) shared between classes.
Saving them to parent class -- IData could better.

 * Status is using DMTF CIM 2.23.0Final Schema:
     CIM_ManagedSystemElement['OperationalStatus']
 * Enable Status is using DMTF CIM 2.23.0Final Schema:
     CIM_EnabledLogicalElement['EnabledState']

Currently, Volume/Pool/System classese are still using their own ways and
not compatible with this patch, we will change them after fully tested.

Thanks Tony for pointing out the missing get_key().

libstorage/libstoragemgmt,cathay4t/libstoragemgmt,jumitche/libstoragemgmt,libstorage/libstoragemgmt,lazy404/libstoragemgmt,joehandzik/libstoragemgmt,HP-Scale-out-Storage/libstoragemgmt,cathay4t/libstoragemgmt,tasleson/libstoragemgmt,jumitche/libstoragemgmt,lazy404/libstoragemgmt,cathay4t/libstoragemgmt,HP-Scale-out-Storage/libstoragemgmt,joehandzik/libstoragemgmt,HP-Scale-out-Storage/libstoragemgmt,tasleson/libstoragemgmt,tasleson/libstoragemgmt,jumitche/libstoragemgmt,tasleson/libstoragemgmt,libstorage/libstoragemgmt,jumitche/libstoragemgmt,lazy404/libstoragemgmt,joehandzik/libstoragemgmt,lazy404/libstoragemgmt,jumitche/libstoragemgmt,libstorage/libstoragemgmt,cathay4t/libstoragemgmt,tasleson/libstoragemgmt,joehandzik/libstoragemgmt,libstorage/libstoragemgmt,cathay4t/libstoragemgmt,HP-Scale-out-Storage/libstoragemgmt