include property documentation in the index

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>
Do basic master housekeeping

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>
remove remaining == None

sa does not allow is None in the whereclauses,
we create a simple null constant for usage inside the db apis

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>